Relationships and Calculus Unit Test Revision R&C Assessment Standard 1.1 1. A function f is defined by the formula 𝑓(𝑥) = 3𝑥 3 − 14𝑥 2 + 13𝑥 + 6 where x is a real number (a) Show that x - 2 is a factor of f ( x ). (2) (b) Hence factorise f ( x) fully. (2) (c) Solve f ( x) 0. (2) 2. A function f is defined by the formula 𝑓(𝑥) = 2𝑥 3 − 5𝑥 2 − 22𝑥 − 15 where x is a real number (a) Show that x + 1 is a factor of f ( x ). (2) (b) Hence factorise f ( x) fully. (2) (c) Solve f ( x) 0. (2) 3. A function f is defined by the formula 𝑓(𝑥) = 𝑥 3 − 4𝑥 2 + 𝑥 + 6 where x is a real number 4. (a) Show that x + 1 is a factor of f ( x ). Hence factorise f ( x) fully. (4) (b) Hence solve x3 - 4x2 + 5x – 2 = 4x - 8 (#2.1,1) Solve the cubic equation f ( x) 0 given the following: when f ( x) is divided by x – 5 , the remainder is zero when the graph of y f ( x) is drawn, it passes through the point (-4,0) x + 1 is a factor of f ( x) . 5. Solve the cubic equation f ( x) 0 given the following: when f ( x) is divided by x + 3, the remainder is zero when the graph of y f ( x) is drawn, it passes through the point (-1,0) x + 2 is a factor of f ( x) . 6. (#2.2) (#2.2) The graph of the function 𝑓(𝑥) = 𝑥 2 − 5𝑥 + (𝑘 + 6) does not touch or cross the x-axis. What are the possible values for k ? (#2.1, 2) 7. The graph of the function 𝑓(𝑥) = 𝑘𝑥 2 + 2𝑥 − 1 does not touch or cross the x-axis. What are the possible values for k ? (#2.1, 2) R&C Assessment Standard 1.2 1. Solve 2 cos 2xo = 1 in the interval 0 ≤ x ≤ 180 (3) 2. Solve 2 sin 2xo = √3 in the interval 0 ≤ x ≤ 180 (3) 3. Solve cos 2to – cos to = 0 in the interval 0 ≤ t ≤ 180 (4) 4. Solve sin 2to – cos to = 0 in the interval 0 ≤ t ≤ 180 (4) 5. Given 3 cos xo - sin xo = √10 cos (x – 18.4) o solve 3 cos xo - sin xo = 2.4 for 0 < x < 90 (3) Given 5 sin xo + cos xo = √26 cos (x – 78.7) o solve 5 sin xo + cos xo = 1.3 for 0 < x < 360 (3) 6 7 Solve sin xo cos 20o + cos xo sin 20o = 0.75 for 0 x 180. (#2.1, 2) R&C Assessment Standard 1.3 (Exercise 6F 20-27) 1. Find f x , given that 𝑓(𝑥) = 5√𝑥 + 2. Find f x , given that 𝑓(𝑥) = 8√𝑥 + 3 3. 𝑓(𝑥) = √𝑥 − 2𝑥 5 + 4 √𝑥 6 𝑥3 3 𝑥5 , 𝑥 > 0. , 𝑥 > 0. - 3, 𝑥 ≥ 0. (3) (3) (3) Find and expression for f x (Exercise 6R) 4. A bowler throws a cricket ball vertically upwards. The height (in metres) of the ball t seconds after it is thrown can be represented by the formula h = 10t – 2t2. The velocity of dh the ball at time t is given by v . dt (2) a) Find the velocity of the cricket ball after three seconds. b) Explain your answer in terms of the ball’s movement. (#2.2) 5. A bowler throws a cricket ball vertically upwards. The height (in metres) of the ball t seconds after it is thrown can be represented by the formula h = 8t – 3t2. The velocity of the dh ball at time t is given by v . dt (2) a) Find the velocity of the cricket ball after one second. (#2.2) b) Explain your answer in terms of the ball’s movement. 6. The vertical displacement of a golf ball can be modelled by s = 20t -5t2, where s metres is 𝑑𝑠 the height of the ball t seconds after being struck. The velocity of the ball is given by 𝑑𝑡 . Find the velocity of the golf ball after 3 seconds. (2) (Exercise 14B) 7. Differentiate the function f(x) = 8cosx with respect to x. (1) 8. Differentiate the function f(x) = 7sinx with respect to x. (1) 9. Differentiate the function f(x) = 4sinx with respect to x. (1) (Exercise 6J) 10. A curve has equation y = 2x2 - 4x +3. Find the equation of the tangent to the curve at the point where x = -1. (4) 11. A curve has equation y = 3x2 - 5x +2. Find the equation of the tangent to the curve at the point where x = 2. (4) 12. A curve has equation y = 2x2 -14x +53. Find the equation of the tangent to the curve at the point where x = 8. (4) R&C Assessment Standard 1.4 (Exercise 9H Q3, 9I) 1 1. Find ∫(5𝑥 4 + 1 2 𝑥4 2. Find ∫(4𝑥 3 − ) 𝑑𝑥, 𝑥 > 0. 2 𝑥3 ) 𝑑𝑥, 𝑥 > 0. (4) (4) (Exercise 9Q, 14J) 3. ℎ′ (𝑥) = (𝑥 − 6)-5, find ℎ (𝑥), 𝑥 ≠ 6. (2) ℎ′ (𝑥) = (𝑥 − 2)-4, find ℎ (𝑥), 𝑥 ≠ 2. (2) 4. (Exercise 14C) 5. Find ∫ 5𝑠𝑖𝑛𝑥 𝑑𝑥. 6. Find ∫ 3𝑐𝑜𝑠𝑥 𝑑𝑥 (1) (1) (Exercise 14J Q1,4) 3 4 4 3 7. Find ∫−1( 𝑥 − 2) dx 8. Find ∫−1( 𝑥 + 2) dx (3) (3) Answers R&C Assessment Standard 1.1 1. 2. 3 1 know to use x = 2 and state conclusion 2 know to divide by (x – 2) (b) (x - 2)(3x2 - 8x - 3) (x - 2)(3x + 1)(x - 3) 3 obtain quadratic factor complete factorisation (c) x =3, 2, - ⅓ 5 interpret and solve equation (a) Remainder = 0 so (x+1) is a factor 1 2 know to use x = 1 and state conclusion know to divide by (x – 1) (b) (x +1)(2x2 - 7x - 15) (x + 1)(2x + 3)(x - 5) (c) x = -1, - 3/2 , 5 3 4 5 obtain quadratic factor complete factorisation interpret and solve equation (a) Remainder = 0 so (x - 2) is a factor 4 (a) Remainder = 0 so (x +1) is a factor •1 (x3 - 4x2 + x + 6) ÷ (x + 1) •2 •3 (x + 1)(x -2)(x – 3) stated explicitly •4 Know to use x 1 and state conclusion Know to divide by x + 1 Obtain quadratic factor Factorise completely (b) x3 - 4x2 + x + 6 = 0 stated explicitly #2.1 x = -1, x=2, x=3 •5 State solution 4. x = 5, x = -4, x = -1 #2.2 communicate solution from the context 5. x = -3, x = -1, x = -2 #2.2 communicate solution from the context 6. b2 – 4ac< 0 #2.1 know to, and use, discriminant correctly a = 1 b = -5 c=k+6 2 (-5) – 4 x 1 x (k + 6) < 0 4k > 1 k > 0.25 1 b2 – 4ac< 0 #2.1 know to, and use, discriminant correctly a=kb=2 c = -1 2 (2) – 4 x k x (-1) < 0 4k < -4 k < -1 1 7. solve inequality solve inequality R&C Assessment Standard 1.2 1 2 start to solve solve for 2x 3 solve for x 2. 2x = sin-1(√3/2) 2x = 60o 1 2 start to solve solve for 2x x = 30o and 60o 3 solve for x 3. Using cos2t=2cos2t-1 and substituting 2cos2t – cost – 1 = 0 (2cost + 1)(cost – 1)=0 cost = -1/2 cost = 1 o o t = 0 , 120 1 2 3 4 start to solve factorise solve for one factor solve for second factor 4. Using sin2t=2 sint cost and substituting 2 sint cost – cost = 0 cost(2 sint – 1)=0 cost = 0 sint = 1/2 t = 30o, 90o, 150o 1 2 3 4 start to solve factorise solve for one factor solve for second factor 5. cos(x – 18.4)o= 2.4/√10 x – 18.4o = 40.6 1 2 Form equation and start to solve solve for x-18.4o 3 obtain angles 1 2 Form equation and start to solve solve for x-78.7o 3 obtain angles 1. 2x = cos-1(1/2) 2x = 60o x = 30o and 150o x = 59o 6. cos(x – 78.7)o= 1.3/√26 x – 78.7o = 75.2o x = 153.7o 7. sin (x + 20)=0.75 48.6oand 131.4o 28.6o and 111.4o # 2.1 Express in standard form sin(x+a)o and equate 1 Solve equation for one value of x+20 2 Process solutions for x R&C Assessment Standard 1.3 1 1. 𝑓(𝑥) = 5𝑥 2 + 6x-3 5 𝑓 ′ (𝑥) = x-1/2 + … 1 prepare to differentiate 𝑓 ′ (𝑥) = … -18x-4 3 differentiates second term correctly 2 differentiates first term correctly 2 1 1 prepare to differentiate 2 differentiates first term correctly 3 differentiates second term correctly 2. 𝑓(𝑥) = 8𝑥 2 + 3x-5 𝑓 ′ (𝑥) = 4 x-1/2 + … 𝑓 ′ (𝑥) = … -15x-6 1 −1 3. 𝑓(𝑥) = 𝑥 3 - 2x5 + 4𝑥 2 - 3 1 𝑓 ′ (𝑥) = x-2/3 - 10x4 … 3 𝑓 ′ (𝑥) = … - 2x-3/2 4. 10 - 4t v = -2 m/s ball is moving downwards 5. 8 - 6t v = 2 m/s ball is moving upwards 6. 20 – 10t v = -10 m/s 1 prepare to differentiate 2 differentiates two terms correctly 3 differentiates third term correctly 1 differentiates 2 substitutes #2.2 explaining a solution 1 differentiates 2 substitutes #2.2 explaining a solution 1 differentiates 2 substitutes 7. d(8cosx) = -8sinx dy 1 differentiates correctly 8. d(7sinx) = 7cosx dy 1 differentiates correctly 9. d(4sinx) = 4cosx dy 1 differentiates correctly 𝑑𝑦 1 differentiates correctly 10. 11. 𝑑𝑥 = 4𝑥 − 4 m = -8 y=9 y -9 = -8(x + 1) 2 finds gradient 3 finds y 4 equation of tangent 𝑑𝑦 1 differentiates correctly 2 finds gradient 3 finds y 4 equation of tangent = 6𝑥 − 5 m=7 y=4 y -4 = 7(x-2) 𝑑𝑥 𝑑𝑦 = 4𝑥 − 14 m = 18 y=5 y - 69 = 18(x -8) 12. 𝑑𝑥 1 differentiates correctly 2 finds gradient 3 finds y 4 equation of tangent R&C Assessment Standard 1.4 1 1. ∫( 5𝑥 4 + 2𝑥 −4 ) 𝑑𝑥 5 1 prepares to integrate 2 integrates first term correctly 3 integrates second term correctly 4 includes constant of integration = 4𝑥 4 … 2 …. - 3 𝑥 −3 +c 1 2. ∫( 4𝑥 3 − 2𝑥 −3 ) 𝑑𝑥 4 1 prepares to integrate 2 integrates first term correctly 3 integrates second term correctly 4 includes constant of integration = 3𝑥 3 … … . + 𝑥 −2 +c 3. (𝑥 − 6)−4 1 … x - 4 …+ 𝑐 1 start to integrate 2 complete integration 4. (𝑥 − 2)−3 1 … x - 3 …+ 𝑐 1 start to integrate 2 complete integration 5. -5cosx + c 1 integrates correctly 6. 3sinx + c 1 integrates correctly 7. (𝑥−2)5 5 1 5 (3 − 2)5 − 1 integrates 1 5 (−1 − 2)5 3 evaluate definite integral 48.8 8. (𝑥+2)4 4 1 4 (4 + 2)4 − 323.75 2substitutes limits 1 integrates 1 4 (−1 + 2)4 2substitutes limits 3 evaluate definite integral