AP CALCULUS AB CHAPTER 3 REVIEW A particle in motion moves along the x-axis so its position at time, t, is given by: s(t)=t3-8t2+17t-10. (time in seconds and s(t) in feet) For example: s(0)=-10 means at time t=0, the particle is 10 units to the left of the origin. A particle in motion moves along the x-axis so its position at time, t, is given by: s(t)=t3-8t2+17t-10 A graphical look at s(t): s(t)=t3-8t2+17t-10 1. Determine the average velocity on [1,5]. s(t)=t3-8t2+17t-10 1. Determine the average velocity on [1,8]. Average velocity= changein position change in time or s(t)=t3-8t2+17t-10 1. Determine the average velocity on [1,8]. Average velocity= changein position change in time or s(8) − s(1) 126 − 0 = = 18 feet per second 8 −1 8 −1 *Change in position can also be refered to as “displacement” Determine the instantaneous velocity at t=8. Determine the instantaneous velocity at t=8. Instantaneous velocity is s’(8) s(t)=t3-8t2+17t-10 Determine the instantaneous velocity at t=8. Instantaneous velocity is s’(8) s’(t)=3t2-16t+17 s(t)=t3-8t2+17t-10 Determine the instantaneous velocity at t=8. Instantaneous velocity is s’(8) s’(t)=3t2-16t+17 s’(8)=382-168+17=81 ft/sec s(t)=t3-8t2+17t-10 Determine the instantaneous velocity at t=8. Instantaneous velocity is s’(8) Graphically: s(t)=t3-8t2+17t-10 When does the particle change directions? When does the particle change directions? When s’(t)=0 and changes signs: + to – or – to + When does the particle change directions? When s’(t)=0 and changes signs: + to – or – to + When does the particle change directions? When s’(t)=0 and changes signs: + to – or – to + When does the particle change directions? When s’(t)=0 and changes signs: + to – or – to + Use nDeriv or algebraically find the derivative!! What is the acceleration at t=4? What is the acceleration at t=4? Acceleration at t=4 is s”(4) The second derivative of position What is the acceleration at t=4? Acceleration at t=4 is s”(4) s(t)=t3-8t2+17t-10 What is the acceleration at t=4? Acceleration at t=4 is s”(4) s(t)=t3-8t2+17t-10 s’(t)=3t2-16t+17 What is the acceleration at t=4? Acceleration at t=4 is s”(4) s(t)=t3-8t2+17t-10 s’(t)=3t2-16t+17 s”(t)=6t-16 What is the acceleration at t=4? Acceleration at t=4 is s”(4) s(t)=t3-8t2+17t-10 s’(t)=3t2-16t+17 s”(t)=6t-16 s”(4)=64-16=8 ft per sec2 Write the equation of the line through the origin and the local max on f(x)=4sin(2x) Write the equation of the line through the origin and the local max on f(x)=4sin(2x) Write the equation of the line through the origin and the local max on f(x)=4sin(2x) Use your calculator to find the local max. Write the equation of the line through the origin and the local max on f(x)=4sin(2x) (.785,4) (0,0) Use your calculator to find the local max. Write the equation of the line through the origin and the local max on f(x)=4sin(2x) (.785,4) (0,0) Use your calculator to find the local max. 4−0 slope = .785 − 0 Answer: y-0=4/.785(x-0) or y-4=4/.785(x-.785) Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 8x+4y=12 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 8x+4y=12 4y=-8x+12 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 8x+4y=12 4y=-8x+12 y=-2x+3 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 8x+4y=12 4y=-8x+12 y=-2x+3 Slope=-2 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 Let 12x-3=-2 8x+4y=12 4y=-8x+12 y=-2x+3 Slope=-2 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 Let 12x-3=-2 12x=1 8x+4y=12 4y=-8x+12 y=-2x+3 Slope=-2 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. Locate where f’(x)=the slope of line 8x+4y=12 f ’(x)=12x-3 Let 12x-3=-2 12x=1 1 x= 12 8x+4y=12 4y=-8x+12 y=-2x+3 Slope=-2 Find where f(x)=6x2-3x is parallel to the line 8x+4y=12. A graphical look: #47 page170: The amount A in grams of radioacitve plutonium remaining in a 20-gram sample after t days is given by the formula: A=20(1/2)(t/140) At what rate is the plutonium decaying when t=2 days? Rate is refering to the derivative, A’ ,at t=2. Find the derivative algebraically or use dy/dx on your calculator: Answer: -.098 grams per day