Cracking The Ap Calculus ab Exam 2018

(Marvins-Underground-K-12) #1

(^) ∫eu du
Evaluate the integral to get
eu + C
Now substitute back to get
e^3 x
2



  • C




  1. B Use u-substitution. Here, u = 3x^3 + 2 and du = 9x^2 dx. Then, ∫ x^2 sin (3x^3 + 2) dx = (^) ∫ sin x dx
    = (−cos u) + C = + C. Replace u for the final solution: + C.




  2. C First take the derivative of f(x): f′(x) = . In order for f(x) to be




differentiable  for all real    values, both    pieces  of  f(x)    must    be  equal   at  x   =   −1  and both    pieces  of

f′(x)    must    be  equal   at x    =   −1.     Therefore,  plug   x    =   −1  into    both   f(x)     and    f′(x):  f(−1)    =  

    and f′(−1)  =    .  When    the two parts   of  f(−1)   are set equal   to

each    other,  10  =   −5a −   b   and when    the two parts   of  f′(−1)  are set equal   to  each    other,  −4  =   13a

+   3b. When    this    system  is  solved, a   =   −13 and b   =   55.


  1. C Here we need to use the Product Rule, which is


If  f   (x) =   uv, where   u   and v   are both    functions   of  x,

then    f′(x)   =   u   +   v

Here    we  get

f′(x)   =   x^2 (−2 sin 2x) +   2x(cos  2x)


  1. A Notice how this limit takes the form of the definition of the derivative, which is

Free download pdf