Ch4.1A – Radian and Degree Measure r Ch4.1A – Radian and Degree Measure s θ ~3.14 arcs = half circle r θ = 1 radian One radian – the measure of the angle when the arc length = the radius 1 revolution (360˚) = 2π radians (~6.28 arc lengths) ½ revolution ( ¼ revolution ( )= )= radians radians 1/3 revolution ( )= radians 1/8 revolution ( )= radians Ch4.1A – Radian and Degree Measure s θ r θ = 1 radian One radian – the measure of the angle when the arc length = the radius 1 revolution (360˚) = 2π radians (~6.28 arc lengths) ½ revolution (180˚) = π radians ¼ revolution (90˚) = radians 2 1/3 revolution (60˚) = 1/8 revolution (45˚) = 3 radians radians 4 13 Ex1) Find the acute angle equivalent to 6 Ex2) Find the negative angle equivalent to 3 4 Ex3) Find the positive angle equivalent to 2 3 Ex4) Find the complement and supplement angles to 2 a) 5 4 b) 5 Degree/Radian Conversions Degree/Radian Conversions 90 rad 2 60 rad 3 45 rad 4 30 rad 6 0 0 rad 360 2 rad 180 rad 3 270 rad 2 Conversions: 180 rad 1 rad 180 Conversion Factor: rad 180 or rad 180 Ex5) Convert: a) 135˚ b) -270˚ c) 2 rad d) 2 rad (Quiz on conv in 2 days) Ch4.1A p318 5-19odd,45-55odd Ch4.1A p318 5-19odd,45-55odd Quiz tomorrow! (On conversions) Ch4.1A p318 5-19odd,45-55odd Quiz tomorrow! (On conversions) Ch4.1A p318 5-19odd,45-55odd Quiz tomorrow! (On conversions) Ch4.1A p318 5-19odd,45-55odd Quiz tomorrow! (On conversions) Ch4.1A p318 5-19odd,45-55odd Quiz tomorrow! (On conversions) Ch4.1A p318 5-19odd,45-55odd Quiz tomorrow! (On conversions) Ch4.1B – Arc Length (Quiz tomorrow!) r Ch4.1B – Arc Length r Length of a circular arc: s = r.θ (θ must be in radians) Ex1) A circle has a radius of 4inches. What is the arc length intercepted by a central angle of 240˚. Linear speed: distance traveled Angular speed: time d v t angle swept out time omega Ex3) The second hand of a clock is 10.2cm long. Find the speed of the second hand. t (θ must be in radians) Ex3) A lawn roller is 30in in diameter and makes 1 revolution every 5/6 sec. a) Find the angular speed b) How fast does it move across the lawn? Ch4.1B p319 35-41odd, 52,54,71-81odd,91,95 (Do #35 and #39 in class) (Quiz tomorrow on conversions!) Ch4.1B p319 35-41odd, 52,54,71-81odd,91,95 (Did #35 and #39 in class) (Quiz today on conversions!) Ch4.1B p319 35-41odd, 52,54,71-81odd,91,95 (Did #35 and #39 in class) (Quiz today on conversions!) Ch4.1B p319 35-41odd, 52,54,71-81odd,91,95 (Did #35 and #39 in class) (Quiz today on conversions!) Ch4.1B p319 35-41odd, 52,54,71-81odd,91,95 (Did #35 and #39 in class) (Quiz today on conversions!) Ch4.1B p319 35-41odd, 52,54,71-81odd,91,95 (Did #35 and #39 in class) (Quiz today on conversions!) Ch4.1 Quiz Convert radians to degrees: A B C 1. rad 2. 3. 2 3 11 6 1. 2 rad 5 2. 6 5 3. 3 Convert degrees to radians: A B 4. 270˚ 4. 90˚ 5. 60˚ 5. 30˚ 6. 210˚ 6. 240˚ 1. 2. 2 Name___________ D rad 3 1. rad 2 2. 6 4 3. 3 3 7 3. 6 C 4. 180˚ 5. 120˚ 6. 330˚ D 4. 360˚ 5. 150˚ 6. 300˚ Ch4.2 – The Unit Circle x2 + y2 = 1 Ex1) 45˚ = _____ rad x = _____ y = _____ Ex2) 60˚ = _____ rad x = _____ y = _____ Ex3) 30˚ = _____ rad x = _____ y = _____ Ex4) 0˚ = _____ rad x = _____ y = _____ Ex5) 90˚ = _____ rad x = _____ y = _____ Ex6) x = _____ y = _____ x = _____ y = _____ x = _____ y = _____ x = _____ y = _____ Trig Functions (sine) sin t = y (cosine) cos t = x Ex7) Eval 3 trigs for: a) t 6 b) 5 t 4 c) t d) 3 t 2 Ch4.2A p328 1-39odd (only sin,cos,tan) (tangent) y tan t = x Ch4.2A p328 1-39odd (only sin,cos,tan) Ch4.2A p328 1-39odd (only sin,cos,tan) Ch4.2A p328 1-39odd (only sin,cos,tan) Ch4.2A p328 1-39odd (only sin,cos,tan) Ch4.2B – Trig Functions 1 (cosecant) csc t = y 1 (secant) sec t = x x (cotangent) cot t = y sin t = y cos t = x tan t = y x Ex8) Eval 6 trigs for: t 3 sin t = y cos t = x y tan t = x Ex9) Eval: 13 6 a) sin 7 2 b) cos 1 csc t = y 1 sec t = x x cot t = y x = cos t y = sin t Domains: (what you put in for t) Ranges: (what you get out for x or y) Types of functions: 1. x = cos t is an even function (So is secant) 2. y = sin t is an odd function (So is tan, csc, and cot) Ex10) Use calc: a) sin 76.4˚ (must be in degree mode.) b) cot 1.5 (must be in radian mode.) Ch4.2B p328 57, 2-38 (eoe) Ch4.2B p328 57, 2-38 (every other even) Ch4.2B p328 57, 2-38 (every other even) Ch4.2B p328 57, 2-38 (every other even) Ch4.2B p328 57, 2-38 (every other even) Ch4.2B p328 57, 2-38 (every other even) Ch4.3 – Right Triangle Trig Quiz tomorrow on this! opposite Θ adjacent SOH-CAH-TOA sin θ = cos θ = tan θ = Ch4.3 – Right Triangle Trig opposite SOH-CAH-TOA Θ adjacent opp sin θ = hyp adj cos θ = hyp opp tan θ = adj hyp csc θ = opp hyp sec θ = opp adj cot θ = opp Ex1) Eval 6 trigs for: 5 Θ 3 4 Ch4.3 – Right Triangle Trig opposite SOH-CAH-TOA Θ adjacent opp sin θ = hyp adj cos θ = hyp opp tan θ = adj hyp csc θ = opp hyp sec θ = opp adj cot θ = opp Ex2) Find the value of sin45˚, cos45˚, tan45˚ 45˚ Ex3) Use the equilateral triangle to find the value of sin60˚, cos60˚, sin30˚, cos30˚ Sine, Cosine, and Tangent of Special Angles 1 sin30˚ = 2 2 sin45˚ = 2 3 cos30˚ = 2 2 cos45˚ = 2 3 sin60˚ = 2 1 cos60˚ = 2 3 tan30˚ = 3 tan45˚ = 1 tan60˚ = 3 HW#8) Find exact values of 6 trigs for: 3 Θ 6 Ch4.3A p338 1-22(a,b) Quiz tomorrow – would u like 2 c a sample? Sine, Cosine, and Tangent of Special Angles 1 sin30˚ = 2 2 sin45˚ = 2 3 cos30˚ = 2 2 cos45˚ = 2 3 sin60˚ = 2 1 cos60˚ = 2 3 tan30˚ = 3 tan45˚ = 1 tan60˚ = 3 HW#8) Find exact values of 6 trigs for: 3 Θ 6 Ch4.3A p338 1-22(a,b) Quiz tomorrow – would u like 2 c a sample? Trigonometry & Vector Components S in O pp H yp C os A dj H yp T an O pp A dj opp sinΘ = hyp adj cosΘ = hyp opp tanΘ = adj Ch4.3A p338 1-22(a,b) Quiz today! Ch4.3A p338 1-22(a,b) Ch4.3A p338 1-22(a,b) Ch4.3A p338 1-22(a,b) Ch4.2 Quiz Find exact values:˚ A 1. sin 30˚ 2. tan 30˚ 3. cos 60˚ 4. tan 45˚ 5. sin 60˚ 6. cos 45˚ B 1. cos 30˚ 2. tan 60˚ 3. sin 60˚ 4. cos 45˚ 5. cos 60˚ 6. tan 45˚ Name___________ C 1. sin 60˚ 2. sin 30˚ 3. tan 45˚ 4. cos 60˚ 5. tan 30˚ 6. cos 45˚ D 1. cos 60˚ 2. cos 30˚ 3. tan 30˚ 4. sin 60˚ 5. tan 45˚ 6. sin 45˚ Ch4.3B – Trig Identities Reciprocals: 1 sin θ = csc 1 cos θ = sec 1 tan θ = cot 1 csc θ = sin 1 sec θ = cos 1 cot θ = tan Combos: sin tan cos Pythag: sin 2 cos2 1 1 tan 2 sec2 1 cot 2 csc2 cos cot sin Quiz in 2 days on these identities. Ex4) Let θ be acute angle, with sin θ = 0.6, find: a) cos θ b) tan θ θ˚ Ex5) Let θ be acute, with tan θ = 3, find: a) cot θ b) sec θ θ˚ Ex6) Use a calc to eval: a) cos 28˚ b) sec 28˚ c) sec 5˚40’ Ex7) Find the value of θ in radians and degrees: 3 a) sin θ = 2 2 b) cos θ = 2 b) csc θ = 2 Ex8) Use calc to find θ in: a) degrees for cos θ = 0.3746 b) radians for sin θ = 0.3746 Ch4.3B p339 23-31odd,37-40all(a only),47-55all(a only) Quiz in 2 days Ch4.3B p339 23-31odd,37-40all(a only), 47-55all(a only) Ch4.3B p339 23-31odd,37-40all(a only), 47-55all(a only) Ch4.3B p339 23-31odd,37-40all(a only), 47-55all(a only) Ch4.3C – Trig Word Problems (Quiz on ID’s tomorrow!) Ex7) A surveyor is standing 50ft from the base of a large tree. The surveyor measures the angle of elevation to the top of the tree as 71.5˚. How tall is the tree? h=? θ=71.5˚ | --------50ft-----------| Ex8) A person is 200yds straight away from a river. The person walks at an angle, going 400yds til he gets to the river’s edge. At what angle did he walk? 200yds 400yds Ex9) A 12 meter flagpole casts a shadow 9 meters long. What is the angle of elevation to the sun? Ch4.3C p33924-32even,68-70all,81,82 Quiz tomorrow. Would u like to c an example? Quiz example: 1 = csc 1 = tan sin cos _____ cos 2 1 1 _____ sec2 Ch4.3C p33924-32even,68-70all,81,82 Ch4.3C p33924-32even,68-70all,81,82 Ch4.3C p33924-32even,68-70all,81,82 Ch4.3C p33924-32even,68-70all,81,82 Ch4.3 – Identities Quiz Reciprocals A B 1. 2. 1 sec 1 cot Combinations 3. sin cos Pythag 4. 1 csc Name__________ C D 1 tan 1 cot 1 sin 1 tan 1 cos cos sin sin cos cos sin sin 2 ___ 1 1 ___ sec2 ___ cos2 1 1 cot2 ___ 5. 1 tan 2 2 2 2 1 ___ csc sin ___ 1 ___ cos 1 ___ Ch4.4A – Trig Functions of Any Angle (x,y) Ch4.4A – Trig Functions of Any Angle (x,y) r Reminder: QII sinθ = cosθ = tanθ = QIII sinθ = cosθ = tanθ = θ y sin θ = r x cos θ = r y tan θ = x r csc θ = y r sec θ = x x cot θ = y QI sinθ = cosθ = tanθ = QIV sinθ = cosθ = tanθ = Ex1) Let -3,4 be a point on the terminal side of an angle θ. find sin,cos,tan. 5 4 Ex2) Given tan θ = . and cos θ > 0. Find sin θ and sec θ. Ex3) Evaluate sin and tan at 0, 3 , , 2 2 Reference Angles - any given angle has an equivalent angle where 0 > θ > 90˚ , or 0 > θ > π/2. Ex4) Find ref angle: a) 300˚ b) 2.3 c) -135˚ Ex5) Evaluate:4 a) cos 3 c) csc Quiz in 2 days (Ex?) b) tan (-210˚) 11 4 Ch4.4A p349 2-42eoe (all 6 trigs) Sample Quiz for Ch4.2/4.3 1. 7 sin 6 2. cos(135 ) 3. sin(135 ) 4. 5. 6. 7. 8. 5 cos 6 2 sin 3 cos(270 ) sin(300 ) cos( ) Lab4.1 – Heights and Lengths (angles measured) Ch4.4A p349 2-42eoe (all 6 trigs) Ch4.4A p349 2-42eoe (all 6 trigs) Ch4.4A p349 2-42eoe (all 6 trigs) Ch4.4A p349 2-42eoe (all 6 trigs) Lab4.1 – Heights and Lengths (angles measured) Ch4.4B – More Trigs at Any Angle 1 Ex6) Let θ be an angle in QII, such that sinθ = 3 Find cos θ and tan θ using trig identities. Ex7) Use a calculator to evaluate: a) cot (410˚) b) sin (-7) c) Solve for θ: tan θ = 4.812, where 0 < θ < 2π Ch4.4B p350 43-81odd (a only) Quiz tomorrow! Ch4.4B – More Trigs at any Angle HW#43) Eval sin,cos,tan for: a) 225˚ #63) Find 2 values in degrees and radians a) sin θ = ½ , where 0 < θ < 2π Ch4.4B p350 43-81odd (a only) Quiz tomorrow! Ch4.4B p350 43-81odd (a only) Ch4.4B p350 43-81odd (a only) Ch4.4B p350 43-81odd (a only) Ch4.4B p350 43-81odd (a only) Ch4.5A – Graphs of Sine and Cosine (Quiz first) Ex1) What are the values of sine and cosine at: θ sin θ cos θ 0 6 4 3 2 3 2 2 Ch4.5A – Graphs of Sine and Cosine (Quiz first) Ex1) What are the values of sine and cosine at: θ sin θ cos θ 0 0 1 1 2 3 2 6 4 3 2 3 2 2 2 2 2 2 3 2 1 2 1 0 0 -1 -1 0 0 1 Ex2) Graph on a # line: y = sin x Ex3) Graph on a # line: y = cos x y = a.sin x y = a.cos x Amplitude – stretches and shrinks graph vertically Ex4) Sketch y = 2.sin x θ 0 2 3 2 2 2.sinx y = a.sin x y = a.cos x Amplitude – stretches and shrinks graph vertically Ex5) Sketch y = ½.cos x θ ½.cos x 0 2 3 2 2 Period of Sine and Cosine (Normally its 2π) y = a.sin (bx) y = a.cos (bx) b determines the period 2 period b Ex6) Sketch y = sin(½x) vs y = sin (x) vs y = sin(2x) 1 –1 Ch4.5A p361 1–13odd, 43,45 2 3 2 2 3 4 Ch4.5A p361 1–13odd, 43,45 Ch4.5A p361 1–13odd, 43,45 Ch4.5A p361 1–13odd, 43,45 Ch4.5A p361 1–13odd, 43,45 Ch4.5B – Translations y = a.sin(bx – c) y = a.cos(bx – c) a = amplitude b determines the period c = horizontally shifts the period 2 period b Ex7) Sketch y = ½.sin(x start: bx – c = 0 end: bx – c = 2π – ) 3 2 3 2 2 Ex8) y = 3.cos(2πx + 1) Use a calc to find its period Ex9) Sketch y = 2.cos(2x – π) + 1 Ch4.5B p361 15–21odd,47–53odd (lets do 17 and 47 in class) Ch4.5B p361 15–21odd,47–53odd Ch4.6A – Graphs of Other Functions Ex1) Sketch the graph of y = tan x θ tan θ 0 4 2 3 2 2 4 Ch4.6A – Graphs of Other Functions Ex1) Sketch the graph of y = tan x θ tan θ 0 4 2 3 2 2 0 1 undefined 0 undefined 0 2 2 To find asymptotes for tangent: bx c bx c 2 2 x Ex2) Sketch the graph of y = tan 2 θ tan θ 0 4 2 3 2 2 4 To find asymptotes for tangent: bx c bx c 2 2 Ex3) Sketch the graph of y = –3tan2x θ tan θ 0 4 2 3 2 2 4 To find asymptotes for tangent: bx c bx c 2 2 Ex4) Sketch the graph of y = cot x θ cot θ cot 0 4 2 3 2 2 4 cos sin x Ex5) Sketch the graph of y = 2cot 3 θ cot θ 0 4 2 3 2 2 4 Ch4.6A p372 9-12,21,22,24 To find asymptotes for cotangent: bx c 0 bx c Ch4.6A p372 9-12,21,22,24 Ch4.6B – Graphs of Other Functions Ex6) Sketch the graph of y = csc x θ sin x csc x 0 4 2 3 2 2 To find asymptotes for cosecant: anywhere sin x = 0 Ex7) Sketch the graph of y = sec x θ cos x sec x 0 4 2 3 2 2 To find asymptotes for secant: anywhere cos x = 0 HW#13) Sketch the graph of y = -½sec x HW#19) Sketch the graph of y = csc Ch4.6B p372 13-20all,23,26 x 2 Ch4.6B p372 13-20all,23,26 Ch4.7 – Inverse Trig Functions Ex1) Graph y = sin x 1 - - 2 -1 2 3 2 2 Ch4.7 – Inverse Trig Functions Ex1) Graph y = sin x 1 - - 2 -1 2 3 2 2 The inverse function of sin x is called sin-1 x or arcsin x - its domain is [-1,1], and its range is . Graph arcsin x 2 , 2 y r If sin θ = If sin-1 y r =θ then sine is taking an angle and giving us the ratio of the side opposite to the hypotenuse. then inverse sine is taking the ratio of the sides and giving us the angle Ex2) a) Find the exact value of arcsin(- ½) 3 b) Find the exact value of arcsin( ) 2 c) Find the exact value of arcsin(2) Ex3) Graph y = cos x 1 - - 2 -1 2 3 2 Graph y = arccos x Ex4) Find the exact value of arccos(½) Find the exact value of arccos ( 3 ) 2 2 Ex5) Graph y = tan x 1 - - 2 -1 2 3 2 2 Graph y = tan-1 x Ex6) Find the approx value of tan-1 (.7042) Ch4.7A p383 7-19odd (a,b),23,25 Ch4.7A p383 7-19odd (a,b),23,25 Ch4.7A p383 7-19odd (a,b),23,25 Ch4.7B – Inverse Trig Functions cont x Ex6) Graph y = sin 2 1 - Graph y = sin-1 - x 2 2 -1 2 3 2 2 Inverse properties sin(arcsin x) = x cos(arccos x) = x tan(arctan x) = x arcsin(sin x) = x arccos(cos x) = x arctan(tan x) = x Ex7) Find the exact value of tan(arctan(-5)) 5 Find the exact value of arcsin(sin ) 3 Ch4.7B p383 8-20even (a only),27-41odd Ch4.7C – Inverse Trig Functions cont Ex7) Find the exact value of a. tan(arccos( 2 ) 5 3 b. cos(arcsin( ) 5 Ex8) Write each as an algebraic expression: a. sin(arccos(3x) 0 < x < 1/3 b. cot(arccos(3x) 0 < x < 1/3 Ch4.7C p385 34-42even,43-51odd,71,75 Ch4.7C p385 34-42even,43-51odd,71,75 Ch4.8A – Applications B Ex1) Solve the triangle: a A 34.2˚ b = 19.4 C Ex2) The maximum angle for a ladder is 72˚. If a fire dept’s longest ladder is 110ft, what is the max rescue height? h=? 72˚ Ex3) At a point 200ft from the base of a building, the angle of elevation to the bottom of a smoke stack is 35˚. The angle of elevation to the top of the smoke stack is 53˚. Find the height of the smoke stack. h=? 53˚ 35˚ Ex4) Find the angle of depression to the bottom of a pool. 20m 1.3m 3.9m Ch4.8A p394 1-11odd,18 Ch4.8A p394 1-11odd,18 Ch4.8B – Applications Ex5) A ship leaves a port with a heading of N54˚W traveling at 20mph. Ship 2 leaves port at the same tjme with a heading N36˚E traveling at 30mph. After 2 hours how far apart are they? HW#35) An observer in a lighthouse 350ft above sea level observes 2 ships directly offshore. The angle of depression to the ships are 4˚ and 6.5˚. How far apart are the ships? 4˚ Ch4.8B p395 17-37odd 6.5˚ Lab4.2 – Finding Angles Ch4.8B p395 17-37odd Ch4.8B p395 17-37odd Ch4.8B p395 17-37odd Ch4.8C – Simple Harmonic Motion (SHM) 10cm 0cm -10cm 10cm 0cm -10cm d = a.sinωt |a| = amplitude 2 = period = frequency 2 or d = a.cosωt Ex6) a) Write an equation for the SHM of a ball attached to a spring, that is pushed up 10cm, and oscillates with a period of 4sec. b) Find the frequency. 3 6cos[ 4 Ex7) Given a spring in SHM described by: d = find: a) Period b) Frequency c) Where is the ball located when t = 4? d) Find 2 times where d = 0. t] Lab4.3 – Simple Harmonic Motion Go over HW quickly HW: Finish lab questions + Ch4 Rev#1 p401 1-53eoe Ch4 Rev#2p402 61,65,69,73,75,77, 87,93,97,99,103,104,105,107 Ch4.8C p398 20,49-56all,58 (let’s do 52 and 56 in class #20 on next slide) Ch4 Rev#1 p401 1-53eoe Ch4 Rev#2p402 61,65,69,73,75,77, 87,93,97,99,103,104,105,107 Ch4 Rev#1 p401 1-53eoe Ch4 Rev#1 p401 1-53eoe Ch4 Rev#1 p401 1-53eoe Ch4 Rev#2p402 61,65,69,73,75,77,87,93,97,99,103,104,105,107 Ch4 Rev#2p402 61,65,69,73,75,77,87,93,97,99,103,104,105,107 6 5 4 3 2 1 -6 -5 -4 -3 -2-1 -1 -2 -3 -4 -5 -6 12 3 4 5 6