Mr. Beck Review Sheet Test Lines Vertical Lines have no slope. (0 in denominator is undefined) Horizontal Lines have 0 slope. 𝑥 +𝑥 𝑦 +𝑦 Midpoint formula: ( 1 2 2 , 1 2 2 ) Slope formula: 𝑚 = 𝐶ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑋 PreCalc 𝐶ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑌 Parallel lines have the same slope. Perpendicular lines have slopes of negative reciprocal. Distance formula: 𝑑 = √(𝑥2 − 𝑥1 )2 + (𝑦2 − 𝑦1 )2 Point Slope Form: 𝑦 − 𝑦1 = 𝑚(𝑥 − 𝑥1 ) Form of line: 𝑦 = 𝑚𝑥 + 𝑏 System of Equations can have: A. Infinite solutions- (Same Equation) 𝑦 = 3𝑥 − 7 2𝑦 = 6𝑥 − 14 B. Parallel- (Never meet, therefore no solutions) 𝑦 = 3𝑥 + 2 𝑦 = 3𝑥 + 5 C. 1 Solution𝑦 = 3𝑥 − 1 𝑦 = −𝑥 + 5 What is a function? A set of ordered pairs where for each element in the domain there is only 1 element in the range. Vertical line test can be used to identify function Standard form of a Parabola 𝑦 = 𝑎(𝑥 − ℎ)2 + 𝑘 (ℎ, 𝑘) = 𝑡𝑢𝑟𝑛𝑖𝑛𝑔 𝑝𝑜𝑖𝑛𝑡 −𝑏 Axis of Symmetry 𝑥 = 2𝑎 Form of parabola: 𝑦 = 𝑎𝑥 2 + 𝑏𝑥 + 𝑐 Completing the Square- Ex: 𝑦 = 𝑥 2 + 4𝑥 + 5 𝑦 = (𝑥 2 + 4𝑥 + 4) + 5 − 4 𝑦 = (𝑥 + 2)2 + 1 Polynomial Functions- Exponents only whole numbers𝑦 = 3𝑥 2 + 2𝑥 + 4 -All real numbers Rational Expression- Negative Exponents- Mr. Beck 2 Review Sheet PreCalc 2 𝑦 = 3𝑥 2 + 𝑥 + 4 - All real numbers except zero Any Polynomial: 𝑦 = 𝑎𝑛 𝑥 𝑛 + 𝑎𝑛−1 𝑥 𝑛−1 + 𝑎𝑛−2 𝑥 𝑛−2 … + 𝑎2 𝑥 2 + 𝑎1 𝑥1 + 𝑎0 Synthetic DivisionStep 1- Take Divider such as (X-2) and separate to just -2 Step 2- Change to positive 2, so that you can add instead of subtracting Step 3- Set up and divide. Last number is remainder Ex: 𝑥 3 + 3𝑥 2 − 4𝑥 + 7 ÷ (𝑥 − 2) = 𝑥 2 + 5𝑥 + 6 𝑅19 1 3 -4 7 1 5 6 R-19 Remainder TheoremIf 𝑃(𝑥) ÷ (𝑥 − 𝑎) then P(a) is the remainder Factor TheoremFor P(x), if P(a)=0, then x-a is a factor of the dividend. Cubic Equations If Positive- If Negative- Quartic Equations If Positive- - W If Negative-- M If tangent at one point, one of the roots is double, ex: (𝑥 + 2)2 Descartes’ Rule of Signs- The number of positive roots of P(x)=0 is either equal to the number of variations in sign of P(x) or is less then this number by a positive even integer The number of negative roots of P(x) is equal to the number of variations in sign of P(-x). Mr. Beck Review Sheet PreCalc Ex: P(x)=−2𝑥 4 + 𝑥 3 − 7𝑥 2 + 4𝑥 + 1 P(-x)= −2𝑥 4 − 𝑥 3 − 7𝑥 2 − 4𝑥 + 1 3 or 1 Possible Positive Values 1 Possible Negative Value 2 Possible Complex Values GLB and LUB Step 1- Set up Synthetic Division Step 2- Start with positive numbers, 1…2…3…, until you get all non-negative values. That is the LUB. Step3- Start with the negative numbers, -1….-2….-3….., until you get values with alternating signs. That is the GLB. (zero doesn’t count as a positive value). Polynomial Theorems1. The Fundamental Theorem of Algebra- For P(x) of degree n, P(x)=0 has exactly n roots. (provided that double roots are counted twice, etc.) ex: 2𝑥 4 − 𝑥 3 − 7𝑥 2 − 4𝑥 + 1 has 4 roots. 2. Complex Conjugates- If P(x) is polynomial with real coefficients and a+bi is a complex root of P(x)=0 then a-bi is also a root. 3. Square Root Conjugates- If 𝑎 + √𝑏 is a root, then 𝑎 − √𝑏 is also a root. 4. Real Root- If P(x) is a polynomial of odd degree (n) with real coefficient, then P(x)=0 has at least 1 real root. (Location Principle- If P(a)<0 and P(b)>0, there must be at least 1 zero between a and b). −𝑏 5. Sum and Product of Roots- for P(x)=𝑎𝑥 2 + 𝑏𝑥 + 𝑐, Sum of roots= 𝑎 , 𝑐 Product of Roots= 𝑎. Rational Root TheoremFor 𝑎𝑛 𝑥 𝑛 + 𝑎𝑛−1 𝑥 𝑛−1 + ⋯ + 𝑎0 = 0 = (𝑞𝑥 − 𝑝) 𝑝 (Q must divide 𝑎𝑛 and p must divide 𝑎0 , 𝑡ℎ𝑒𝑛 𝑥 = 𝑞 𝑖𝑠 𝑎 𝑟𝑜𝑜𝑡 And therefore any rational root must be a factor of 𝑎0 Domain and RangeDomain- Possible values of the first element in an ordered pair. Range- Possible values of the second element in an ordered pair. Extracting a Function from a CompositionWhen given a function and you need to find x. Ex: 𝑓(𝑥 − 3) = 𝑥 2 − 11𝑥 + 24 𝐿𝑒𝑡 𝑈 = 𝑥 − 3 𝑥 =𝑢+3 𝑓(𝑥) = (𝑢 + 3)2 − 11(𝑢 + 3) + 24 𝑎 𝑛 Mr. Beck Review Sheet PreCalc 𝑓(𝑥) = 𝑢2 + 6𝑢 + 9 − 11𝑢 − 33 + 24 𝑓(𝑥) = 𝑢2 − 5𝑢 𝑓(𝑥) = 𝑥 2 − 5𝑥 Translation Functions If you Replace y with –y- Reflect over x axis. Ex: 𝑓(𝑥) → −𝑓(𝑥) If you Replace x with –x- Reflect over y axis. Ex: 𝑓(𝑥) → 𝑓(−𝑥) If you Replace (x,y) with (-x,-y)- Symmetrical over the Origin. If you Add to X move to Left, If you Subtract from X move to Right. Ex: 𝑓(𝑥) → 𝑓(𝑥 + 1) 𝑓(𝑥) → 𝑓(𝑥 − 1) If you Add to Y move Up, If you subtract from Y move down. 𝑓(𝑥) → 𝑓(𝑥) + 1 𝑓(𝑥) → 𝑓(𝑥) − 1 Absolute Value- Reflect Negative Values over x axis. Exchange x and y, reflection over line y=x Multiply Y by 2 Stretch Vertically, Multiply X by 2 Shrink Horizontally 𝑓(𝑥) → 2𝑓(𝑥) 𝑓(𝑥) → 𝑓(2𝑥) Sine Curve: Cosine Curve: Graphing of Trig Functions 𝑦 = 𝑎𝑠𝑖𝑛𝑏𝑥 a= amplitude, |a| max 𝑣𝑎𝑙𝑢𝑒−min 𝑣𝑎𝑙𝑢𝑒 a= 2 b= Frequency 2𝜋 𝑃𝑒𝑟𝑖𝑜𝑑 = 𝐹𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 𝑦 = √𝑥 Mr. Beck Review Sheet PreCalc Inverse of a Function: Definition- 2 Functions, f and g are inverses of each other if for every point (a,b) in f, is (b,a) in g. To find inverse switch x and y, then solve for y. Inverses are a reflection over the line y=x 𝐼𝑓 𝑦𝑜𝑢 𝑡𝑎𝑘𝑒 𝑓[𝑓 −1 (𝑥)] 𝑜𝑟 𝑓 −1 [𝑓(𝑥)] 𝑡ℎ𝑒 𝑟𝑒𝑠𝑢𝑙𝑡 𝑤𝑖𝑙𝑙 𝑎𝑙𝑤𝑎𝑦𝑠 𝑏𝑒 𝑥 𝑎𝑛𝑑 𝑡ℎ𝑒𝑦 𝑤𝑖𝑙𝑙 𝑏𝑒 𝑖𝑛𝑣𝑒𝑟𝑠𝑒𝑠. 𝐼𝑓 𝑡ℎ𝑒 𝑖𝑛𝑣𝑒𝑟𝑠𝑒 𝑜𝑓 𝑎 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 𝑖𝑠 𝑎𝑙𝑠𝑜 𝑎 𝑓𝑢𝑛𝑡𝑖𝑜𝑛 𝑡ℎ𝑒𝑛 𝑤𝑒 𝑠𝑎𝑦 𝑖𝑡 𝑖𝑠 𝑎 𝑜𝑛𝑒 𝑡𝑜 𝑜𝑛𝑒 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛. Line must pass both Horizontal and vertical line test for inverse to be a one to one function. Form FunctionLabel all knowns and unknowns Create two equations and solve (use substitution) Volume of Rectangular Shape=(𝑙𝑒𝑛𝑔𝑡ℎ)(𝑤𝑖𝑑𝑡ℎ)(ℎ𝑒𝑖𝑔ℎ𝑡) Volume of Parallelepiped = (area of base)(height) Volume of Cone= Volume of Sphere= 3 𝜋𝑟 3 𝜋𝑟 2 ℎ 3 4 A Parallelepiped is any figure with any shape based and walls coming up Vertically. Factoring- (Anything can be factored)Ex: 𝑥 − 9 = (√𝑥 + 3)(√𝑥 − 3) 𝑥 2 + 6 = (𝑥 + 𝑖√6)(𝑥 − 𝑖√6) Factoring with negative exponentsIn negative exponents, factor out the less of the two numbers Ex: (𝑥 2 − 25)2 + 2(𝑥 2 + 25)−2 − 8(𝑥 2 − 25)−2 (𝑥 2 − 25)−2 [(𝑥 2 − 25)2 + 2(𝑥 2 + 25) − 8] 𝐴(𝑡) = 𝐴0 (1 ± 𝑟)𝑡 (use only when talking about years) Compound Interest- 𝐴(𝑡) = 𝐴0 (1 + 𝑘)𝑘𝑡 1 1 3 3 𝑟 A(t)= final amount A0= initial amount r= rate k= number of times compounded per year. t= number of years Compounded continuously Mr. Beck Review Sheet 𝐴(𝑡) = 𝐴0 𝑒 𝑟𝑡 A(t)= Final amount A0= initial amount R= rate T= number of years Half Life Decay/Exponential Growth 𝐴(𝑡) = 𝐴0 (2)𝑘 1 𝑡 𝑘 = 𝐻𝑎𝑙𝑓𝑙𝑖𝑓𝑒 𝑑𝑒𝑐𝑎𝑦 𝑡 𝐴(𝑡) = 𝐴0 (𝑟)𝑘 r=rate at which exponentially growths k= how often it grows exponentially Exponential Functions 𝑓(𝑥) = (𝑎)(𝑏 𝑥 ) The Definition of e The irrational number e is defined as: 1 𝑒 = 𝑡ℎ𝑒 𝑙𝑖𝑚𝑖𝑡 𝑒 𝑎𝑠 𝑛 → ∞ (1 + 𝑛)𝑛 𝑒 = lim (1 + 𝑛) 1 𝑛 𝑛→∞ Log Rules 𝐿𝑜𝑔𝑏 𝐴𝐵 = 𝐿𝑜𝑔𝑏 𝐴 + 𝐿𝑜𝑔𝑏 𝐵 (Product rule) 𝐴 𝐿𝑜𝑔𝑏 (𝐵) = 𝐿𝑜𝑔𝑏 𝐴 − 𝐿𝑜𝑔𝑏 𝐵 (Quotient Rule) 𝐿𝑜𝑔(𝑋 𝑛 ) = 𝑛𝑙𝑜𝑔(𝑥) (Power Rule) 𝐿𝑜𝑔𝑏 1 = 0 𝐿𝑜𝑔𝑏 𝑏 = 1 𝑙𝑛1 = 0 𝑙𝑛𝑒 = 1 𝑙𝑜𝑔𝑏𝑎𝑠𝑒 (𝑎𝑛𝑠𝑤𝑒𝑟) = 𝑝𝑜𝑤𝑒𝑟 log(term)= defined when Term>0 undefined when Term≤0 𝑏 log𝑏 𝑥 = 𝑥 Circle (𝑥 − ℎ)2 + (𝑦 − 𝑘)2 = 𝑟 2 𝐴𝑥 2 + 𝐵𝑥𝑦 + 𝐶𝑦 2 + 𝐷𝑦 + 𝐸𝑦 + 𝐹 = 0 In order to be a circle, A and C must be equal. F is negative Ellipse PreCalc Mr. Beck Review Sheet 𝑥2 To find foci, 𝑐 2 = |𝑎2 − 𝑏 2 | 𝑎2 PreCalc 𝑦2 + 𝑏2 = 1 (𝑥−1)2 New Center is (1,5) Hyperbola- The locus of all points, the difference of whose sums from 2 fixed points (foci) is a constant. 𝑥2 To find foci, 𝑐 2 = 𝑎2 + 𝑏 2 To find asymptotes, use box methods. Go from the origin, the value of x and up the value of y in all four directions. Draw a box and make the lines. Then find equation using origin and one of the vertexes of the box. 𝑎2 + (𝑦−5)2 𝑏2 =1 𝑦2 − 𝑏2 = 1 𝑎2 ParabolaA locus of all points equidistant from a line (directrix) and a given point (focus). Parabola has only one focus, which is in the curve. 𝑦 = 4𝑝 𝑦= Consider the equation 𝐴𝑥 2 + 𝐵𝑥𝑦 + 𝐶𝑦 2 + 𝐷𝑥 + 𝐸𝑦 + 𝐹 = 0. If A, B, and C are not all 0 and if graph is not degenerate, then: 1. The graph is the circle or an ellipse if 𝐵 2 − 4𝐴𝐶 < 0; (In a circle, B = 0 and A = C.) 2. The graph is a parabola if 𝐵 2 − 4𝐴𝐶 = 0; 3. The graph is a hyperbola if 𝐵 2 − 4𝐴𝐶 > 0 Trigonometry 𝒚 𝐬𝐢𝐧(𝜽) = 𝒓 𝑥2 (𝑥−ℎ)2 4𝑝 +𝑘 𝒙 𝐜𝐨𝐬(𝜽) = 𝒓 𝒚 𝐭𝐚𝐧(𝜽) = 𝒙 𝒓 𝐜𝐬𝐜(𝜽) = 𝒚 𝒓 𝐬𝐞𝐜(𝜽) = 𝒙 𝒙 𝐜𝐨𝐭(𝜽) = 𝒚 Degrees-Minutes-Seconds 51° 28′ 57" 28 57 51 𝐷𝑒𝑔𝑟𝑒𝑒𝑠 + 60 𝑚𝑖𝑛𝑢𝑡𝑒𝑠 + 3600 𝑠𝑒𝑐𝑜𝑛𝑑𝑠 Reference Angles If In Quadrant I- It is the acute angle If in Quadrant II- 180°-θ If in Quadrant III- 180°+θ If in Quadrant IV- 360°- θ Mr. Beck Review Sheet PreCalc Radians- Radian- measurement of an angle and a number value. Co-Terminal Angles- 2 angles whose terminal ray is in the same position. Quadrantal Angles- 90, 180, 270, 360 10 10 = 1 radian 10 10 Radian= central angle of intercepted arc is the same as the radius. 𝑠 𝜃=𝑟 𝐴𝑛𝑔𝑙𝑒 𝑖𝑛 𝑟𝑎𝑑𝑖𝑎𝑛𝑠 = Converting between Degrees and Radians 𝐴𝑛𝑔𝑙𝑒 𝑖𝑛 𝑑𝑒𝑔𝑟𝑒𝑒𝑠 𝑅𝑎𝑑𝑖𝑎𝑛𝑠 = 𝜋 180° 𝑙𝑒𝑛𝑔𝑡ℎ 𝑜𝑓 𝑎𝑟𝑐 𝑟𝑎𝑑𝑖𝑢𝑠 90/-270 Students Sin and Csc positive All All are positive Quadrant II Quadrant I 0/360 180/-180 Take Tan and Cot are positive Calculus Cos and Sec are positive Quadrant III Quadrant IV 270/-90 Special Right Triangles 1 45 √2 45 1 √3 30 2 1 60 Mr. Beck Review Sheet PreCalc High Leg- If Hypotenuse and Leg of right triangle congruent, therefore triangles congruent. CPCTC- Corresponding Parts of Congruent Triangles Congruent. Inverse Trig FunctionsNote: If capital letter, then limited to Principal domain. (Only one answer). Note: If lowercase letter, than there is no limit (more than one Graphing of Inverse Trigonometric answer). Functions Angle of Inclination tan(𝛼) = 𝑚 Step 1: Get positive reference angle Step 2: Determine whether obtuse or acute angle. (If positive than acute, If negative obtuse). Step 3- Find supplement if needed. Sine Curve Cosine Curve 1. y=arc sin(x) a. Domain- −1 ≤ 𝑥 ≤ 1 𝜋 𝜋 b. Range- − ≤ 𝑦 ≤ 2 2 2. y=arc cos(x) a. Domain- −1 ≤ 𝑥 ≤ 1 b. Range- 0 ≤ 𝑦 ≤ 𝜋 3. y=arc tan(x) a. Domain- −∞ < 𝑥 < ∞ 𝜋 𝜋 b. Range- − < 𝑦 < 2 2 4. y=arc csc(x)a. Domain- 𝑥 ≤ −1 𝑜𝑟 𝑥 ≥ 1 𝜋 𝜋 b. Range- − ≤ 𝑦 ≤ 𝑦 ≠ 0 2 2 5. y=arc sec(x)a. Domain- 𝑥 ≤ −1 𝑜𝑟 𝑥 ≥ 1 𝜋 b. Range- 0 ≤ 𝑦 ≤ 𝜋, 𝑦 ≠ 2 6. y=arc cot(x)a. Domain- −∞ < 𝑥 < ∞ b. Range- 0 < 𝑦 < 𝜋 Tan Curve Mr. Beck Review Sheet Period- The number of radians needed for a complete cycle of a curve. 2𝜋 𝑃𝑒𝑟𝑖𝑜𝑑 = 𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 Period of: Sin Curve: 2𝜋 Cos Curve: 2𝜋 Tan Curve: 𝜋 Frequency- The amount of full cycles with 2𝜋 radians. 𝑦 = 2 sin(𝑥) (𝑎𝑚𝑝𝑙𝑖𝑡𝑢𝑑𝑒 𝑖𝑠 2) 𝑦 = sin(2𝑥) 𝑔𝑒𝑡𝑠 𝑠ℎ𝑟𝑢𝑛𝑘𝑒𝑛 (𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 𝑖𝑠 2 𝑎𝑛𝑑 𝑝𝑒𝑟𝑖𝑜𝑑 𝑖𝑠 𝜋) Identities Reciprocal Identities 1 sin(𝜃) = csc(𝜃) cos(𝜃) = sec(𝜃) tan(𝜃) = cot(𝜃) Quotient Identities sin(𝜃) tan(𝜃) = cos(𝜃) cot(𝜃) = Pythagorean Identities 𝑠𝑖𝑛2 (𝜃) + 𝑐𝑜𝑠 2 (𝜃) = 1 𝑡𝑎𝑛2 (𝜃) + 1 = 𝑠𝑒𝑐 2 (𝜃) 𝑐𝑜𝑡 2 (𝜃) + 1 = 𝑐𝑠𝑐 2 (𝜃) sin(−𝜃) = − sin(𝜃) cos(−𝜃) = cos(𝜃) tan(−𝜃) = −tan(𝜃) 1 1 cos(𝜃) sin(𝜃) PreCalc Mr. Beck Review Sheet PreCalc Vectors Vector- a directed distance. It has a magnitude and a direction. Adding and Subtracting Vectors: v u u+v -v u u-v Multiplying by a Scaler- It can change magnitude or turn it in the other direction. Absolute value of vector is its length. Compass Directions0° N 270° W 90° E 180° S Component form Vector AB (2,3) A(4,-6) and B(-2,-4) then AB (-6, 2) To get vector= (𝑥2 − 𝑥1 ), (𝑦2 − 𝑦1 ) To get magnitude= √(𝑥2 − 𝑥1 )2 , (𝑦2 − 𝑦1 )2 Ex: Mr. Beck Review Sheet V (2,1) W(1,1) 2W-3V (4,2)-(6,3)= (-2,-1) V+W= (3,2) Vector and Parametric Equations of Lines Vector Equation ⃗⃗⃗⃗⃗ 𝑂𝑃 = ⃗⃗⃗⃗⃗ 𝑂𝐴 + ⃗⃗⃗⃗⃗⃗⃗ 𝑡𝐴𝐵 (𝑥, 𝑦) = (𝑥0 , 𝑦0 ) + 𝑡(𝑎, 𝑏) Parametric Equation 𝑥 = 𝑥0 + 𝑡𝑎 𝑦 = 𝑦0 + 𝑡𝑏 Circle 𝑥 = 𝑟𝑐𝑜𝑠(𝑇) + ℎ 𝑦 = 𝑟𝑠𝑖𝑛(𝑇) + 𝑘 Ex: (𝑥 + 1)2 + (𝑦 − 3)2 = 4 𝑥 = 2 cos(𝑇) − 1 𝑦 = 2 sin(𝑇) + 3 Ellipse 𝑥 = acos(𝑇) + ℎ 𝑦 = 𝑏𝑠𝑖𝑛(𝑇) + 𝑘 𝑥2 Hyperbola If 𝑎2 − 𝑏2 = 1 𝑎2 𝑦2 + 𝑏2 = 1 𝑥2 𝑦2 𝑥 = asec(𝑇) + ℎ 𝑦 = 𝑏𝑡𝑎𝑛(𝑇) + 𝑘 𝑦2 𝑥2 If 𝑎2 − 𝑏2 = 1 𝑥 = btan(𝑇) + ℎ 𝑦 = 𝑎𝑠𝑒𝑐(𝑇) + 𝑘 Height Problems 𝑆(𝑇) = −16𝑡 2 + 𝑉0 𝑡 + 𝑆0 𝑉0 − 𝑖𝑛𝑡𝑖𝑎𝑙 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑆0 − 𝑖𝑛𝑖𝑡𝑖𝑎𝑙 ℎ𝑒𝑖𝑔ℎ𝑡 When asked for Maximum height PreCalc Mr. Beck Review Sheet PreCalc −𝑏 ( 2𝑎 , 𝑦) When asked to find for a certain time, plug in for T. When asked at what time does the object reach a certain height make the height equal to the equation and solve. Polar Coordinate (𝑟, 𝜃) r= length of radius 𝜃= angle traveling on. Converting to and from Polar form (𝑟, 𝜃) = [𝑟𝑐𝑜𝑠(𝜃), 𝑟𝑠𝑖𝑛(𝜃)] 𝑥 = 𝑟𝑐𝑜𝑠(𝜃) 𝑦 = 𝑟𝑠𝑖𝑛(𝜃) 𝑥2 + 𝑦2 = 𝑟2 𝑦 𝑇𝑎𝑛(𝜃) = 𝑥 Polar Equations r=1.5 (a circle) 𝜋 𝜃 = 3 (a line) 𝑟 = 𝑎sin(𝜃) (circle- starts from pole and goes upward. a is diameter) 𝑟 = acos(𝜃) (circle- starts from pole and goes towards the right) Cardioid- makes a cusp 𝑟 = 𝑎 + asin(𝜃) 𝑟 = 𝑎 + acos(𝜃) 𝑵𝒐𝒕𝒆: 𝑾𝒉𝒆𝒏 𝒄𝒉𝒂𝒏𝒈𝒊𝒏𝒈 𝒕𝒉𝒆 𝒔𝒊𝒈𝒏 𝒐𝒇 𝒕𝒉𝒆 𝒇𝒊𝒓𝒔𝒕 𝒏𝒖𝒎𝒃𝒆𝒓, 𝒈𝒓𝒂𝒑𝒉 𝒅𝒐𝒆𝒔𝒏′ 𝒕 𝒄𝒉𝒂𝒏𝒈𝒆. 𝑾𝒉𝒆𝒏 𝒄𝒉𝒂𝒏𝒈𝒊𝒏𝒈 𝒔𝒊𝒈𝒏 𝒐𝒇 𝒄𝒐𝒔 𝒐𝒓 𝒔𝒊𝒏, 𝒕𝒉𝒆𝒏 𝒈𝒓𝒂𝒑𝒉 𝒄𝒉𝒂𝒏𝒈𝒆𝒔. Limacon 𝑟 = 3 + 2 cos(𝜃) [𝑎 > 𝑏] Looped Limacon 𝑟 = 1 + 2 cos(𝜃) [𝑎 < 𝑏] Lemniscate 𝑟 2 = 4cos(2𝜃) (A leminscate looks like an eight) Polar Rose 𝑟 = acos(𝑛𝜃) 𝑊ℎ𝑒𝑛 𝑛 𝑖𝑠 𝑎𝑛 𝑒𝑣𝑒𝑛 𝑛𝑢𝑚𝑏𝑒𝑟, 𝑡ℎ𝑒𝑟𝑒 𝑎𝑟𝑒 2𝑛 𝑟𝑜𝑠𝑒 𝑝𝑒𝑑𝑎𝑙𝑠 When n is an odd number there are n rose pedals. Mr. Beck Review Sheet PreCalc Points required for each graph Circle- 2 points (endpoint and pole) Cardioid- 4 points Limacon- 4 points Looped limacon- 5 points Polar roses- Tips of the roses and pole. Solving a Pair of Polar Equations Either make them equal to each other, or use substitution. When solving a pair of polar equations, always make a sketch to verify answer. Complex Numbers in Polar Form 𝑎 + 𝑏𝑖 = 𝑟𝑐𝑜𝑠(𝜃) + 𝑖𝑟𝑠𝑖𝑛(𝜃) 𝑟 = √𝑎2 + 𝑏 2 𝑟𝐶𝑖𝑠(𝜃) = 𝑟𝑐𝑜𝑠(𝜃) + 𝑖𝑠𝑖𝑛(𝜃) 𝑏 𝑇𝑎𝑛(𝜃) = 𝑎 Multiplying and Dividing by Complex Numbers 𝑟1 𝐶𝑖𝑠(𝜃1 ) × 𝑟2 𝐶𝑖𝑠(𝜃2 ) = 𝑟1 𝑟2 𝐶𝑖𝑠(𝜃1 + 𝜃2 ) 𝑟1 𝐶𝑖𝑠(𝜃1 ) 𝑟 𝐶𝑖𝑠(𝜃 −𝜃 ) = 1 𝑟1 2 𝑟 𝐶𝑖𝑠(𝜃 ) Complex Numbers- Raising/Taking Roots 𝑟 𝑛 𝐶𝑖𝑠(𝑛𝜃) [𝑟𝐶𝑖𝑠(𝜃)]𝑛 = 𝑟 𝑛 𝐶𝑖𝑠( + 𝑘 𝑛 Finding the best fit Curve R should be either close to 1 or -1. Calculator: Step 1- Make sure diagnostics is on Step 2- Clear all lists Step 3- Record all data in the table Step 4- Graph points using ZoomStat and StatPlot Step 5- Decide what is looks like (PowerReg, ExpReg, LineReg, QuadReg) Step 6- Pick the Regression that fits best using the r to determine which is the best fit. Arithmetic and Geometric Sequences Arithmetic- 𝑎𝑛 = 𝑎1 (𝑟)𝑛−1 Geometric- 𝑎𝑛 = 𝑎1 + (𝑛 − 1)𝑑 Sequence on Calculator- 2 2 2 1 1 𝜃 360 𝑛 ) Mr. Beck Review Sheet Seq(f(x), X, Start, End, Step) Sum of Sequences/Series 𝑛(𝑡 +𝑡 ) Arithmetic- 𝑆𝑛 = 12 𝑛 Geometric- 𝑆𝑛 = 1 Infinite Geometric Sum- 𝑆 = 1−𝑟 Sequence of Partial Sums If the sequence of partial sums approaches a Limit L, then the series converges to L. (Must have a target to converge). If r is between 1 and -1, then it converges. Otherwise it diverges. To find the interval of convergence: Ex: 1 + (𝑥 − 2)1 + (𝑥 − 2)2 + (𝑥 − 2)3 … 𝑟 = (𝑥 − 2) −1 < 𝑥 − 2 < 1 1<𝑥<3 LimitsStrategyDivide by the x with biggest exponent in the denominator and solve. 6 𝑖𝑠 𝑢𝑛𝑑𝑒𝑓𝑖𝑛𝑒𝑑 0 𝑡1 (1−𝑟 𝑛 ) 1−𝑟 𝑎 0 𝐿𝑖𝑚𝑖𝑡 𝑟𝑢𝑙𝑒𝑠: 𝐿𝑖𝑚(𝑓 − 𝑔) = lim(𝑓) − lim(𝑔) 𝐿𝑖𝑚(𝑓 + 𝑔) = lim(𝑓) + lim(𝑔) 𝐿𝑖𝑚(𝑓𝑔) = 𝐿𝑖𝑚(𝑓) × 𝐿𝑖𝑚(𝑔) 𝑓 lim(𝑓) 𝐿𝑖𝑚 (𝑔) = lim(𝑔) 0 𝑖𝑠 𝑢𝑛𝑑𝑒𝑓𝑖𝑛𝑒𝑑 𝝐 − 𝜹 𝑫𝒆𝒇𝒊𝒏𝒊𝒕𝒊𝒐𝒏 𝒐𝒇 𝒂 𝒍𝒊𝒎𝒊𝒕 If |𝑓(𝑥) − 𝐿| < 𝜖, 𝑡ℎ𝑒𝑛 0 < |𝑥 − 𝑎| < 𝛿 Sigma Notation 𝑛(𝑛+1) ∑𝑛𝑘=1 𝑘 = 2 ∑𝑛𝑘=1 𝑘 2 = ∑𝑛𝑘=1 𝑘 3 = ( Mathematical Induction Step 1- Test for 1 Step 2- Assume true that n=k. 𝑛(𝑛+1)(2𝑛+1) 6 𝑛(𝑛+1) 2 ) 2 PreCalc Mr. Beck Review Sheet PreCalc Step 3- Change formula to Sk+1 Step 4- Add extra term to both sides and solve. Binomial Theorem Ex: 𝑛(𝑛2 + 5) is a multiple of 6 Step 1- Test for 1 Step 2- Assume n=k is true, and that 𝑛(𝑛2 + 5) is a multiple of 6. Step 3- Make equation for Sk+1 and prove that it is multiple of 6. Piecewise Function −𝑥, 𝑥 < 0 Ex: 𝑓(𝑥) = { 𝑥, 𝑥 ≥ 0 Derivative 𝑓(𝑥+ℎ)−𝑓(𝑥) Definition of Derivative- 𝑀𝑡𝑎𝑛 = lim ℎ Derivative for Specific Value- 𝐹 Power rule- 𝐼𝑓 𝑓(𝑥) = 𝑥 , 𝑡ℎ𝑒𝑛 𝑓 = 𝑛𝑥 𝑑 Product rule- 𝑑𝑥 (𝑓(𝑥)(𝑔(𝑥) = 𝑓(𝑥)𝑔′ (𝑥) + 𝑔(𝑥)𝑓 ′ (𝑥)=(first)(derivative of sec)+(sec)(derivative of first). Quotient rule- 𝑑𝑥 (𝑔) = Continuity Definition- A function is said to be continuous at a point x=c if: 1. lim 𝑓(𝑥) 𝑒𝑥𝑖𝑠𝑡𝑠 2. 𝑓(𝑐)exists 3. lim 𝑓(𝑥) = 𝑓(𝑐) Differentiability Differentiability over an interval implies continuity but continuity over an interval DOESN’T imply differentiability. Squeeze Theoremsin(ℎ) lim =1 ℎ→0 ′ (𝑎) = lim 2 𝑑 𝑓 ′ (𝑥) 𝑔𝑓 ′ −𝑓𝑔′ 𝑔2 = 𝑥→𝑎 𝑓(𝑥)−𝑓(𝑎) 𝑥−𝑎 𝑛−1 (den)(derivative of num)−(num)(derivative of den) (𝑑𝑒𝑛)2 𝑥→𝑐 𝑥→𝑐 ℎ→0 lim ℎ ℎ =1 ℎ→0 sin(ℎ) sin(3𝑥) 3 lim sin(4𝑥) = 4 ℎ→0 lim ℎ→0 lim ℎ→0 1−cos(𝑥) 𝑥 cos(𝑥)−1 𝑥 =0 =0 Derivatives of Trig Functions Mr. Beck Review Sheet 𝑑 sin(𝑥) 𝑑𝑥 𝑑 cos(𝑥) 𝑑𝑥 𝑑 tan(𝑥) 𝑑𝑥 𝑑 cot(𝑥) 𝑑𝑥 𝑑 sec(𝑥) 𝑑𝑥 𝑑 csc(𝑥) 𝑑𝑥 = cos(𝑥) = − sin(𝑥) = sec 2 (𝑥) = −𝑐𝑠𝑐 2 (𝑥) = tan(𝑥) sec(𝑥) = − csc(𝑥) cot(𝑥) Linearization 𝐿(𝑥) = 𝑓(𝑎) + 𝑓′(𝑎)(𝑥 − 𝑎) Pick a point near the one you are trying to estimate. Differentials𝑑𝑦 = 𝑓′(𝑥)(𝑑𝑥) Chain Rule 𝑑𝑦 𝑑𝑦 𝑑𝑢 = (𝑑𝑢)(𝑑𝑥 ) 𝑑𝑥 PreCalc When finding derivative other than x such as: 3cos(𝑥 2 ). Find derivative of the whole term, and then the term on the inside (𝑥 2 ). Implicit Differentiation Finding the derivative when both xs and ys on one side of the equation. 2𝑥 2 𝑦 2 + 𝜋𝐶𝑜𝑠(𝑦) = 𝑥 Rate Problems 1. Relate the variables 2. Eliminate a variable 3. Find the derivative with respect to T 4. Plug in and solve Similar Triangles Graphing (Derivatives, Relative Min and Max, Concavity, Increasing/Decreasing) Step 1: When Give a regular function such as 𝑓(𝑥) = 𝑥 2 + cos(𝑥), check to see where the derivative is undefined. (What value of x makes the function undefined). Find roots of regular function. (Use these values when graphing). Step 2: Check to see if there is a pinhole or an asymptote. 𝑥 2 −4 Pinhole: Where a point on the function is left blank. Ex: 𝑓(𝑥) = 𝑥−2 𝑥 ≠ 2. There is a pinhole at x=2. Asymptote: When the function approaches this line, it either goes to positive or negative infinity. To find vertical asymptote, determine at which value of x, Mr. Beck Review Sheet PreCalc 𝑥 the function will be undefined. Ex: 𝑓(𝑥) = 𝑥−4 𝐴𝑠𝑦𝑚𝑝𝑡𝑜𝑡𝑒 𝑎𝑡 𝑥 = 4. To find the horizontal asymptote make x approach infinity as if it were a limit and 𝑥 𝑋 the value you get for y is the asymptote. Ex: 𝑓(𝑥) = 𝑥−4 . 𝑋 = 1, 𝑡ℎ𝑒𝑟𝑒𝑓𝑜𝑟𝑒 𝑎𝑠𝑦𝑚𝑝𝑡𝑜𝑡𝑒 𝑎𝑡 𝑦 = 1. Step 3: To find where the graph is increasing or decreasing, take the first derivative of the function. Set the first derivative to zero and determine critical values. Label a number line for the 1st derivative and make a number line analysis with those critical values, to determine where the graph is increasing or decreasing. Graph the critical values by plugging them into the original equation. If for a critical value the first derivative goes from positive to negative value, it is a relative maximum, and if for a critical value the first derivative goes from a negative to a positive value, then it is a relative minimum. Step 4: To find concavity, find the second derivative; determine the critical values by setting the 2nd derivative to zero. Then make a number line for the second derivative. A positive value indicates concave up. A negative value indicates concave down. A critical value that is involved in a sign change is an inflection point, unless that value makes the function undefined. Note: Align the two number lines one under the other, to make it easier to compare the two when graphing. It is important to know both whether the graph is decreasing or increasing and concavity. Note: When noting intervals of concavity or increase/decrease, Concavity has only parenthesis since concavity is never including the critical values. Increasing/decreasing is always square brackets, since the critical values are also increasing/decreasing. Positive/Negative infinity never have square brackets, since it is not a “value” that you can technically include. Test 1 Starts Here Absolute Min/Max Conditions: 1. 𝑓 ′ (𝑥) = 0 2. 𝑓 ′ (𝑥) = 𝑑𝑒𝑓𝑖𝑛𝑒𝑑 3. Endpoints To find an absolute min/max, take the function, get its derivative, set the derivative to zero. Once solved, taker the answers and plug into the original equation along with the endpoints. Ex: 2 𝑓(𝑥) = 3 𝑥 3 − 3𝑥 2 + 4𝑥 Interval of [0,3] 𝑓 ′ (𝑥) = 2𝑥 2 − 6𝑥 + 4 2𝑥 2 − 6𝑥 + 4 = 0 2(𝑥 2 − 3𝑥 + 2) = 0 (𝑥 2 − 3𝑥 + 2) = 0 (𝑥 − 2)(𝑥 − 1) = 0 Mr. Beck Review Sheet 𝑥 = 2, 𝑥 = 1 5 𝑓(1) = 3 𝑓(2) = 3 PreCalc 4 𝑓(0) = 0 (absolute min) 𝑓(3) = 3 (absolute max) *Stationary Points- are simply points where 𝑓 ′ (𝑥) = 0 Applied Min/Max Questions 1. Express Quantity As Need (Usually two equations) 2. Optimize for one variable 3. Find derivative 4. Set=0, undefined Test 2 Starts Here Rolle’s Theorem 1. 𝑓(𝑎) = 𝑓(𝑏) = 0 (x-intercepts) 2. Must be continuous on interval [a,b] (including) 3. Differentiable on interval (a,b) (not including) Then there must be at least one value, c, such that 𝑎 ≤ 𝑐 ≤ 𝑏 and 𝑓 ′ (𝑐) = 0. (At least one place where the derivative is zero). Extreme Value Theorem Every function that is continuous must have a maximum and minimum. Mean Value Theorem 1. 𝑓(𝑥) 𝑖𝑠 𝑐𝑜𝑛𝑡𝑖𝑛𝑢𝑜𝑢𝑠 [𝑎, 𝑏] 2. 𝑓(𝑥)𝑖𝑠 𝑑𝑖𝑓𝑓𝑒𝑟𝑒𝑛𝑡𝑖𝑎𝑏𝑙𝑒 (𝑎, 𝑏) 𝑓(𝑏)−𝑓(𝑎) 3. 𝑓 ′ (𝑐) = 𝑏−𝑎 then there must be at least one C, 𝑎 ≤ 𝑐 ≤ 𝑏, such that the slope of tangent=slope of secant Rectilinear Motion—Motion on a Line 𝑠(𝑡) − 𝑝𝑜𝑠𝑖𝑡𝑖𝑜𝑛 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 𝑣(𝑡) − 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 𝑎(𝑡) − 𝑎𝑐𝑐𝑒𝑙𝑒𝑟𝑎𝑡𝑖𝑜𝑛 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 Positive Velocity= moving to the right Negative Velocity= moving to the left Zero Velocity= at rest To get from position to Velocity and from velocity to acceleration functions, you simply take the derivative of the former. Anti-derivative/Integral Infinite Integral Mr. Beck Review Sheet 𝑥 𝑛+1 ∫ 𝑥 𝑛 𝑑𝑥 = 𝑛+1 + 𝐶 𝐹(𝑥) + 𝑐 𝑖𝑠 𝑡ℎ𝑒 𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛 𝑡𝑜 𝑡ℎ𝑒 𝑑𝑖𝑓𝑓𝑒𝑟𝑒𝑛𝑡𝑖𝑎𝑙 𝑒𝑞𝑢𝑎𝑡𝑖𝑜𝑛 𝑖𝑓 𝑎𝑛𝑑 𝑜𝑛𝑙𝑦 𝑖𝑓 𝑡ℎ𝑒 = 𝑑(𝐹(𝑥) = 𝑓(𝑥) 𝑑𝑥 𝒀𝒐𝒖 𝒄𝒂𝒏 𝒂𝒍𝒘𝒂𝒚𝒔 𝒇𝒂𝒄𝒕𝒐𝒓 𝒐𝒖𝒕 𝒂 𝒄𝒐𝒏𝒔𝒕𝒂𝒏𝒕 𝒊𝒏 𝒇𝒓𝒐𝒏𝒕 𝒐𝒇 𝒂𝒏 𝒊𝒏𝒕𝒆𝒈𝒓𝒂𝒍 U Substitution in Integrals Ex: ∫(𝑥 2 + 3)25 2𝑥 𝑑𝑥 𝐿𝑒𝑡 𝑢 = 𝑥 2 + 3 𝑑𝑢 = 2𝑥 𝑑𝑥 ∫ 𝑢25 𝑑𝑢 ∫ *When integrating functions like 𝐶𝑜𝑠(𝑛𝑥) it equals 𝑆𝑖𝑛(𝑛𝑥) +𝑐 𝑛 Gravity Questions 𝑚 𝑓𝑡 𝑔 = 9.8 𝑠𝑒𝑐 2 𝑜𝑟 32 𝑠𝑒𝑐 2 PreCalc (𝑥 2 +3)26 26 Quick Review 𝑑 sin(𝑥) = cos(𝑥) 𝑑𝑥 𝑑 cos(𝑥) = − sin(𝑥) 𝑑𝑥 𝑑 tan(𝑥) = sec 2 (𝑥) 𝑑𝑥 𝑑 cot(𝑥) = −𝑐𝑠𝑐 2 (𝑥) 𝑑𝑥 𝑑 sec(𝑥) = tan(𝑥) sec(𝑥) 𝑑𝑥 𝑑 csc(𝑥) = − csc(𝑥) cot(𝑥) 𝑑𝑥 +𝑐 𝑉(𝑡) = −𝑔𝑡 + 𝑉0 −𝑔𝑡 2 𝑆(𝑡) = 𝑊ℎ𝑒𝑛 𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 𝑖𝑠 𝑍𝑒𝑟𝑜, 𝑡ℎ𝑒𝑛 𝑖𝑠 ℎ𝑎𝑠 𝑟𝑒𝑎𝑐ℎ𝑒𝑑 𝑖𝑡𝑠 ℎ𝑖𝑔ℎ𝑒𝑠𝑡 𝑝𝑜𝑖𝑛𝑡 𝑜𝑟 𝑖𝑠 𝑎𝑡 𝑟𝑒𝑠𝑡 𝑊ℎ𝑒𝑛 𝑝𝑜𝑠𝑖𝑡𝑖𝑜𝑛 𝑖𝑠 𝑍𝑒𝑟𝑜, ℎ𝑖𝑡 𝑡ℎ𝑒 𝑔𝑟𝑜𝑢𝑛𝑑 Area under Graph by Limits of Integration 𝑨 = 𝐥𝐢𝐦 ∑𝒏𝒌=𝟏 𝑭(𝑿𝒌 ) 𝚫𝒙 𝚫𝒙 = Ex: F(x) = 2 − 𝑥 3 [0,1] 1 Δ𝑥 = 𝑛 lim ∑𝑛𝑘=1(2 − [𝑛] ) 𝑛 2 + 𝑉0 𝑡 + 𝑆0 𝒏→∞ 𝒃−𝒂 𝒏 𝑘 3 1 𝑛→∞ 1 (Since there are infinite amount of 2s, then there are 2n. Distribute 𝑛 in next step) 2𝑛 1 2−( 2− 1 𝑘3 − ∑𝑛𝑘=1 [𝑛4 ] 𝑛 Quick Review 𝑛 𝑛(𝑛 + 1) ∑𝑘 = 2 𝑛(𝑛+1) 2 1 ) 2 𝑛4 (𝑛2 +2𝑛+1) 1 4 1 𝑛2 1 1 lim 2 − (4 + 2𝑛 + 4𝑛2 ) 𝑛→∞ 7 𝐴=4 𝑘=1 𝑛 ∑ 𝑘2 = 𝑘=1 𝑛 𝑛(𝑛 + 1)(2𝑛 + 1) 6 ∑ 𝑘3 = ( 𝑘=1 𝑛(𝑛 + 1) 2 ) 2 Mr. Beck Review Sheet PreCalc Area under Graph 𝐹(𝑥) = ∫𝑎 𝑓(𝑥)𝑑𝑥 (Area Function) 𝑇ℎ𝑒 𝑑𝑒𝑟𝑖𝑣𝑎𝑡𝑖𝑣𝑒 𝑜𝑓 𝑡ℎ𝑒 𝑎𝑟𝑒𝑎 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 𝑖𝑠 𝑡ℎ𝑒 𝑏𝑜𝑢𝑛𝑑𝑎𝑟𝑦 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛 Riemann Sums 𝒃 𝑨 = 𝐥𝐢𝐦 ∑𝒏𝒌=𝟏 𝑭(𝑪𝒌 ) 𝚫𝒙 = ∫𝒂 𝒇(𝒙)𝒅𝒙 The Definite Integral: 𝒃 ∫𝒂 𝒇(𝒙)𝒅𝒙 𝐴𝑏𝑎 = 𝐹(𝑐)(𝑏 − 𝑎) 𝐴𝑐𝑎 + 𝐴𝑏𝑐 = 𝐴𝑏𝑎 𝐴𝑏𝑎 − 𝐴𝑐𝑎 = 𝐴𝑏𝑐 𝐴𝑏𝑎 + −𝐴𝑐𝑎 = 𝐴𝑏𝑐 𝐴𝑏𝑎 = −𝐴𝑎𝑏 𝑌𝑎𝑣 = lim ∑𝑛𝑘=1 𝐹(𝑋𝑘 ) (𝑏−𝑎) 𝑌𝑎𝑣 = (𝑏−𝑎) ∫𝑎 𝑓(𝑥)𝑑𝑥 𝑥 𝒎𝒂𝒙𝚫𝑿𝒌 →𝟎 1 𝑛→∞ 1 𝑏 Average value of a function 𝑌𝑎𝑣 = 𝐹𝑎𝑣 𝑑𝑦 = 𝑖𝑛𝑠𝑡𝑎𝑛𝑡𝑎𝑛𝑒𝑜𝑢𝑠 𝑟𝑎𝑡𝑒 𝑜𝑓 𝑐ℎ𝑎𝑛𝑔𝑒 𝑑𝑥 ∆𝑦 (𝑏−𝑎) ∫𝑎 𝑓(𝑥)𝑑𝑥 = 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑣𝑎𝑙𝑢𝑒 Second Fundamental Theorem of Calculus Let f be continuous on an open Interval I, let A be any number in the interval 𝑥 I, if F is defined by 𝐹(𝑥) = ∫𝑎 𝑓(𝑥)𝑑𝑥. Then 𝐹 ′ (𝑥) = 𝑓(𝑥) ∆𝑥 = 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 𝑟𝑎𝑡𝑒 𝑜𝑓 𝑐ℎ𝑎𝑛𝑔𝑒 1 𝑏 Rectangular Approximation MethodNote: Use Δ𝑋 as interval for heights. If 1 1 Δ𝑋 𝑖𝑠 4 , 𝑡ℎ𝑒𝑛 𝑤ℎ𝑒𝑛 𝑝𝑙𝑢𝑔𝑔𝑖𝑛𝑔 𝑖𝑛 𝑋𝑠 𝑓𝑜𝑟 ℎ𝑒𝑖𝑔ℎ𝑡𝑠, 𝑑𝑜 𝑖𝑛 𝑖𝑛𝑡𝑒𝑟𝑣𝑎𝑙𝑠 𝑜𝑓 4. 𝑳𝑹𝑨𝑴/𝑴𝑹𝑨𝑴/𝑹𝑹𝑨𝑴 𝒐𝒏 𝑪𝒂𝒍𝒖𝒍𝒂𝒕𝒐𝒓 = (𝑺𝒖𝒎(𝑺𝒆𝒒(𝑭(𝒙), 𝒙, 𝑺𝒕𝒂𝒓𝒕 𝑷𝒐𝒊𝒏𝒕, 𝑬𝒏𝒅 𝑷𝒐𝒊𝒏𝒕, 𝑰𝒏𝒕𝒆𝒓𝒗𝒂𝒍/ 𝚫𝑿) 𝐿𝑅𝐴𝑀 = Δ𝑋(𝑆𝑢𝑚 𝑜𝑓 𝐻𝑒𝑖𝑔ℎ𝑡𝑠, 𝐿𝑒𝑓𝑡 𝑊𝑎𝑙𝑙 𝑜𝑓 𝐻𝑒𝑖𝑔ℎ𝑡𝑠) Ex: 𝐿𝑅𝐴𝑀 = 4 ⌈𝑒 0 + 𝑒 −(4) + 𝑒 −(2) ⌉, where 𝑓(𝑥) = 𝑒 −𝑥 𝑀𝑅𝐴𝑀 = Δ𝑋(𝑆𝑢𝑚 𝑜𝑓 𝐻𝑒𝑖𝑔ℎ𝑡𝑠, 𝑀𝑖𝑑𝑑𝑙𝑒 𝑜𝑓 𝐻𝑒𝑖𝑔ℎ𝑡𝑠) 1 1 2 1 2 2 Mr. Beck Review Sheet 1 1 2 3 2 5 2 PreCalc Ex: 𝑀𝑅𝐴𝑀 = 4 ⌈𝑒 −(8) + 𝑒 −(8) + 𝑒 −(8) ⌉, where 𝑓(𝑥) = 𝑒 −𝑥 𝑅𝑅𝐴𝑀 = Δ𝑋(𝑆𝑢𝑚 𝑜𝑓 𝐻𝑒𝑖𝑔ℎ𝑡𝑠, 𝑅𝑖𝑔ℎ𝑡 𝑊𝑎𝑙𝑙 𝑜𝑓 𝐻𝑒𝑖𝑔ℎ𝑡𝑠) Ex: 𝑅𝑅𝐴𝑀 = 4 ⌈𝑒 −(4) + 𝑒 −(2) + 𝑒 −(4) ⌉, where 𝑓(𝑥) = 𝑒 −𝑥 Test 3 Starts Here Area Under Curve (Upper-Minus Lower/Right-Left) 1 1 2 1 2 3 2 2 2 f(x) g(x) 𝑏 𝐴 = ∫𝑎 𝑓(𝑥) − 𝑔(𝑥) 𝑑𝑥 Upper – Lower Graphs (Vertical Lines=dx) Right- Left (Horizontal Lines= dy) Ex: 𝑦 = √𝑥, 𝑦 = −𝑥 + 6, 𝑦 = 1 2 𝐴 = ∫1 6 − 𝑦 − 𝑦 2 𝑑𝑦 Volume of Solid by Slices𝑏 𝑉 = ∫𝑎 𝐴(𝑥) 𝑑𝑥 (Depending on the Shape of the slices, the Area formula will be different. For example, Square is 𝑆 2 . 𝐸𝑥: Mr. Beck Review Sheet 𝑥2 + 𝑦2 = 4 Cut Into Square slices Side of Square is equal to 2y 2 𝑉 = ∫−2(2𝑦)2 𝑑𝑥 𝑉 = 4 ∫−2 𝑦 2 𝑑𝑥 (Need to replace y, because can’t solve unless in X) 𝑉 = 4 ∫−2 4 − 𝑥 2 𝑑𝑥 Volume of Revolutions If rotating around x-axis, then dx If rotation around y-axis, then dy 𝑏 𝑏 𝑉 = 𝜋 ∫𝑎 𝑟 2 𝑑𝑥 or 𝑉 = 𝜋 ∫𝑎 𝑟 2 𝑑𝑦 If hole in the disk then Bigger Radius-Smaller Radius. Volume By Shells If rotating around x-axis, then dy If rotating around y-axis, then dx 𝑏 𝑉 = 2𝜋 ∫𝑎 𝑥 𝑓(𝑥) 𝑑𝑥 x= Radius f(x)= height dx= Thickness Whenever doing volume by shells, it is helpful to draw in the cylinder. Length of a Curve 𝑏 𝑑𝑥 𝑑𝑦 𝑠 = ∫𝑎 √[ 𝑑𝑡 ] + ⌈ 𝑑𝑡 ⌉ 𝑑𝑡 (Parametric) 𝑑𝑥 𝑠 = ∫𝑎 √[𝑑𝑦] + 1 𝑑𝑦 𝑏 𝑑𝑦 𝑠 = ∫𝑎 √[𝑑𝑥 ] + 1 𝑑𝑥 Surface Area of a Curve 𝑏 𝑆 = 2𝜋 ∫𝑎 𝑟 𝑑𝑠 Depending on the problem, you use one of the ds. If they give you limits of integration for x, most likely you will use dx. If they give you limits of integration for y, most likely you will use dy. If they give you limits of integration for t, most likely you will use dt. Sum of Terms 2 𝑘 Ex: lim ∑𝑛𝑘=1 𝑛 sin (𝜋 𝑛) 2 2 2 𝑏 2 2 2 𝑛→∞ PreCalc Mr. Beck Review Sheet PreCalc 𝑘 𝑋𝑘 = 𝑛 1 lim ∑𝑛𝑘=1 (𝑛) 2 sin(𝜋𝑥) 𝑛→∞ 1 ∫0 2 sin(𝜋𝑥) 𝑑𝑥 To find limits of integration, find lowest possible x, and highest possible x. Ex: 𝑘 𝑋𝑘 = 𝑛 Lowest= 𝑛=∞ = 0 Highest=𝑛=∞ = 1 Work Two types of Work problems: 𝑊 = (𝑓)(𝑑) 𝑏 𝑊 = ∫𝑎 𝐹(𝑥)𝑑𝑥 𝑊 = ∫𝑎 (𝑑𝑒𝑛𝑠𝑖𝑡𝑦)(𝑉𝑜𝑙𝑢𝑚𝑒)(𝑑𝑖𝑠𝑡𝑎𝑛𝑐𝑒) Density/Specific Gravity of Water= 62.5 Hooke’s Law 𝐹(𝑥) = 𝑘𝑥 𝐹𝑜𝑟𝑐𝑒 = (𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡)(𝑑𝑖𝑠𝑡𝑎𝑛𝑡) Trapezoidal Approximation 𝑌 𝑌 𝑇 = ∆𝑥( 21 + 𝑌2 + 𝑌3 + 𝑌4 + 25 ) New Derivatives and Integrals 𝑑(ln(𝑥)) 1 =𝑥 𝑑𝑥 ∫ 𝑥 𝑑𝑥 = ln(𝑥) ∫ 𝑘=1 𝑘=∞ 𝑏 1 𝑑𝑢 = 𝑙𝑛|𝑢| + 𝑐 𝑢 𝑥 𝑑𝑡 ∫1 𝑡 = ln(𝑥) 1 𝑑𝑡 − ∫𝑥 = ln(𝑥) 𝑡 𝑑𝑎𝑥 = 𝑎 𝑥 (ln(𝑎)) 𝑑𝑥 𝑎𝑥 𝑥 ∫ 𝑎 = ln(𝑎) + 𝑐 𝑑𝑒 𝑥 ∫ 𝑒𝑥 = 𝑒𝑥 + 𝑐 𝑑𝑥 = 𝑒𝑥 Mr. Beck Strange Graphs 𝑦 = ln(𝑥) 𝑦 = 𝑒𝑥 𝑦 = 𝑒 −𝑥 Review Sheet PreCalc Mr. Beck Review Sheet PreCalc Newton’s Method of Approximation Used to estimate the root without calculus 𝑓(𝑥 ) 𝑋𝑛 = 𝑋𝑛−1 − 𝑓′ (𝑋𝑛−1 Using the Calculator 1. Type the function into Y1, ex= 𝑦 = 𝑥 3 − 𝑥 − 1 2. Type the derivative of the function into Y2, ex=𝑦 = 3𝑥 2 − 1 3. Use X value given in problem 4. Store this value as x, ex: 1 → 𝑥 𝑌 5. (𝑥 − 𝑌1 ) → 𝑥 𝑛−1) 2 Write the above into calculator and press answer to get approximation of value. To get another iteration, simply repress enter. Lopital’s Rule If lim (𝑔(𝑥)) = 0 𝑜𝑟 Derivative of the Inverse 1 (𝑓 −1 )′ = 𝑓′ (𝑓−1 (𝑥)) 𝐷𝑒𝑟𝑖𝑣𝑎𝑡𝑖𝑣𝑒 𝑜𝑓 𝐼𝑛𝑣𝑒𝑟𝑠𝑒: 𝑇𝑎𝑘𝑒 𝑑𝑒𝑟𝑖𝑣𝑎𝑡𝑖𝑣𝑒 𝑤𝑖𝑡ℎ 𝑟𝑒𝑠𝑝𝑒𝑐𝑡 𝑡𝑜 𝑦 𝑎𝑛𝑑 𝑡ℎ𝑒𝑛 𝑓𝑙𝑖𝑝 𝑡𝑜 𝑔𝑒𝑡 𝑑𝑒𝑟𝑖𝑣𝑎𝑡𝑖𝑣𝑒 𝑤𝑖𝑡ℎ 𝑟𝑒𝑠𝑝𝑒𝑐𝑡 𝑡𝑜 𝑥 ex: 𝑦 = 𝑥 5 + 7𝑥 3 + 4𝑥 + 1 Quick Review Quick Review 𝑥 = 𝑦 5 + 7𝑦 3 + 4𝑦 + 1 1. y=arc sin(x) Pythagorean Identities 𝑑𝑥 = 5𝑦 4 + 21𝑦 2 + 4 2 (𝜃) 2 (𝜃) a. Domain- −1 ≤ 𝑥 ≤ 1 𝑑𝑦 𝑠𝑖𝑛 + 𝑐𝑜𝑠 =1 𝑓(𝑥) 0 ∞ ∞ 𝑑𝑦 Inverse Trig Functions 𝑑 sin−1 (𝑢) 𝑑𝑥 1 𝑡𝑎𝑛2 (𝜃) + 1 = 𝑠𝑒𝑐 2 (𝜃) 𝑐𝑜𝑡 2 (𝜃) + 1 = 𝑐𝑠𝑐 2 (𝜃) = 5𝑦 4 +21𝑦2 +4 𝑑𝑥 𝑑 cos−1 (𝑢) 𝑑𝑥 𝑑 tan−1 (𝑢) 𝑑𝑥 𝑑 cot−1 (𝑢) 𝑑𝑥 𝑑 sec−1 (𝑢) 𝑑𝑥 𝑑 csc−1 (𝑢) 𝑑𝑥 1 𝑑𝑢 = √1−𝑢2 𝑑𝑥 1 𝑑𝑢 = − √1−𝑢2 𝑑𝑥 1 𝑑𝑢 = 1+𝑢2 𝑑𝑥 1 𝑑𝑢 = − 1+𝑢2 𝑑𝑥 = 1 𝑑𝑢 𝑢√𝑢2 −1 𝑑𝑥 =− 𝑓 ′ (𝑥) 𝑜𝑟 0 ∗ ∞ 𝑡ℎ𝑎𝑛 𝑖𝑛 𝑒𝑞𝑢𝑎𝑙𝑠 lim(𝑔′ (𝑥)) 1 𝑑𝑢 𝑢√𝑢2 −1 𝑑𝑥 Works the other way too 1 Ex: ∫ √1−𝑢2 = sin−1(𝑢) Ex: ∫ 1+𝑢2 = tan−1(𝑢) Integration by Parts 1 𝜋 𝜋 b. Range- − 2 ≤ 𝑦 ≤ 2 2. y=arc cos(x) a. Domain- −1 ≤ 𝑥 ≤ 1 b. Range- 0 ≤ 𝑦 ≤ 𝜋 3. y=arc tan(x) a. Domain- −∞ < 𝑥 < ∞ 𝜋 𝜋 b. Range- − 2 < 𝑦 < 2 4. y=arc csc(x)a. Domain- 𝑥 ≤ −1 𝑜𝑟 𝑥 ≥ 1 𝜋 𝜋 b. Range- − 2 ≤ 𝑦 ≤ 2 𝑦 ≠ 0 5. y=arc sec(x)a. Domain- 𝑥 ≤ −1 𝑜𝑟 𝑥 ≥ 1 𝜋 b. Range- 0 ≤ 𝑦 ≤ 𝜋, 𝑦 ≠ 2 6. y=arc cot(x)a. Domain- −∞ < 𝑥 < ∞ b. Range- 0 < 𝑦 < 𝜋 Mr. Beck Review Sheet ∫ 𝑢𝑑𝑣 = 𝑢𝑣 − ∫ 𝑣𝑑𝑢 To solve, first you must determine what u and dv are. From that you figure out what v and du are. Then you simply plug and solve. Keep in mind you may have to repeat it more than once. Ex: ∫ ln(𝑥) 𝑑𝑥 𝒖 = 𝐥𝐧(𝒙) 𝒅𝒙 𝒅𝒖 = 𝒙 𝒅𝒗 = 𝒅𝒙 𝒗=𝒙 𝑑𝑥 ∫ ln(𝑥) 𝑑𝑥 = ln(𝑥) ∗ 𝑥 − ∫ 𝑥 𝑥 ∫ ln(𝑥) 𝑑𝑥 = 𝑥𝑙𝑛(𝑥) − 𝑥 + 𝑐 Trig Substitutions 1−cos(2𝑥) 𝑆𝑖𝑛2 (𝑥) = 2 𝐶𝑜𝑠 2 (𝑥) = ∫ tan(𝑥) 𝑑𝑥 = −𝑙𝑛|cos(𝑥)| + 𝑐 ∫ sec(𝑥) 𝑑𝑥 = 𝑙𝑛|sec(𝑥) + tan(𝑥)| + 𝑐 ∫ csc(𝑥) 𝑑𝑥 = −𝑙𝑛|csc(𝑥) + cot(𝑥)| + 𝑐 Integration by Trig Substitution By using identities such as: Pythagorean Identities 𝑠𝑖𝑛2 (𝜃) + 𝑐𝑜𝑠 2 (𝜃) = 1 𝑡𝑎𝑛2 (𝜃) + 1 = 𝑠𝑒𝑐 2 (𝜃) 𝑐𝑜𝑡 2 (𝜃) + 1 = 𝑐𝑠𝑐 2 (𝜃) You can solve integrals such as: 1 ∫ √4−𝑥 2 𝑑𝑥 𝑙𝑒𝑡 𝑥 = 2 sin(𝑎) 𝑑𝑥 = 2 cos(𝑎) 𝑑𝑎 4 − 4𝑠𝑖𝑛2 (𝑎) = 4𝑐𝑜𝑠 2 (𝑎) 1 𝑑𝑥 ∫ 2 ∫ √4𝑐𝑜𝑠2 ( ) 𝑑𝑥 2 𝑎 1 ∫ 2 cos(𝑎) 𝑑𝑥 ∫ 2cos(𝑎) 𝑑𝑥 1+cos(2𝑥) √4−4𝑠𝑖𝑛 (𝐴) 1 PreCalc 2cos(𝑎) 𝐴+𝑐 𝑥 𝐴 = 𝑆𝑖𝑛−1 (2) To Define and integrate Improper Integrals Anytime one of the limits of integration are infinity, it is an improper fraction. Mr. Beck Review Sheet Ex: ∞ 𝑑𝑥 𝑏 𝑑𝑥 ∫1 𝑥 2 = lim ∫1 𝑥 2 lim − [𝑥] 1 𝑏→∞ 1 𝑏 𝑏→∞ 1 1 − [𝑏 − 1] = 1 Integration by Partial Fractions Ex: 12𝑥+17 𝐴 𝐵 ∫ (𝑥+1)(𝑥+2) = 𝑋+1 + 𝑋+2 = 𝐴𝑋+2𝐴+𝐵𝑋+𝐵 (𝑋+1)(𝑋+2) 12𝑥 + 17 = (𝐴 + 𝐵)𝑥 + 2𝐴 + 𝐵 𝐴 + 𝐵 = 12 2𝐴 + 𝐵 = 17 A=5 B=7 5 7 + (𝑥+2) (𝑥+1) ∫ (𝑥+1) + (𝑥+2) = 5𝑙𝑛|𝑥 + 1| + 7𝑙𝑛|𝑥 + 2| + 𝑐 Differential Equations 𝑑𝑦 Ex: 𝑑𝑥 = −4𝑥𝑦 2 Initial Condition (f(0)=1) 5 7 𝑑𝑦 ∫ 𝑦 2 = ∫ −4𝑥 𝑑𝑥 − 𝑦 = −2𝑥 2 + 𝑐 PreCalc = −4𝑥 𝑑𝑥 𝑦2 𝑑𝑦 1 −1 = 0 + 𝑐 −1 = 𝑐 1 𝑦 = 2𝑥 2 +1 Slope Fields If horizontal row of slopes doesn’t change, than there is no x in the equation If vertical column of slopes doesn’t change, than there is no y in the equation Euler’s Method 𝑑𝑦 ∆𝑦 ≈ 𝑑𝑥 ∆𝑥