Engineering Board Exam Reviewer · Integration by Parts · hard

Evaluate: x3 ex2,dx

  1. ≤ft(x2 + 1 ) ex22+C
  2. ≤ft(x2 - 1 ) ex2+C
  3. ≤ft(x2 - 1 ) ex22+C
  4. x4 ex24+C

Answer

C. ≤ft(x2 - 1 ) ex22+C

Solution

Write x3ex2=x2· xex2. Let u=x2, dv=xex2dx so v= 12ex2: x3ex2dx= 12x2ex2- xex2dx= 12x2ex2- 12ex2= (x2-1)ex22+C.

More Integration by Parts questions

  1. Evaluate: ≤ft( x )2,dx (assume x>0)
  2. Evaluate: ≤ft(x ),dx
  3. Evaluate: e2 x ≤ft(3 x ),dx
  4. Evaluate: x2 e3 x,dx
  5. Evaluate: x2 ≤ft(x ),dx
  6. Evaluate: x ≤ft(2 x ),dx
  7. Evaluate: x3 x,dx (assume x>0)
  8. Evaluate: x,ex,dx
  9. Evaluate: x x,dx
  10. Evaluate: x,dx

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