AP EAMCET2016MathematicsIndefinite Integration
If x^3 e^ 5 x d x= e^ 5 x 5^4 [f(x)]+C , then f(x) is equal to
Options
- Ax^3 5 - 3 x^2 5^2 + 6 x 5^3 - 6 5^4
- B5 x^3-5^2 x^2+5^3 x-6
- C5^2 x^3-15 x^2+30 x-6
- D5^3 x^3-75 x^2+30 x-6
Correct answer
D. 5^3 x^3-75 x^2+30 x-6
Step-by-step solution
We have given that, x^3 e^ 5 x d x= e^ 5 x 5^4 [ (x) ]+c By using the method of intergration by parts, we get aligned & x^3 e^ 5 x d x=x^3 e^ 5 x d x- d x^3 d x e^ 5 x d x d x & = x^3 e^ 5 x 5 - 3 x^2 e^ 5 x 5 d x+C aligned By using the method of integration by parts, we get aligned & = x^3 e^ 5 x 5 - 3 5 x^2 e^ 5 x d x & + 3 5 d x^2 d x e^ 5 x d x d x+C & = x^3 e^ 5 x 5 - 3 x^3 e^ 5 x 25 + 6 25 x e^ 5 x d x & = x^3 e^ 5 x 5 - 3 x^3 e^ 5 x 25 + 6 x 25 e^ 5 x d x & - 6 25 d x d x e^ 5 x d x d x & = x^3 e^ 5 x 5 - 3