NDA2020MathematicsDefinite IntegrationActual
What is the value of ₀^ / 4 ( ^3 x+ x ) d x ?
Options
- A1 4
- B1 2
- C1
- D2
Correct answer
B. 1 2
Step-by-step solution
aligned I & = ₀^ 4 ( ^3 x+ x ) d x & = ₀^ 4 ^3 x d x+ ₀^ 4 x d x aligned aligned & = ₀^ 4 x ^2 x d x+ ₀^ 4 x d x = & ₀^ 4 x ( ^2 x-1 ) d x+ ₀^ 4 x d x aligned aligned & = ₀^ 4 x ^2 x d x- ₀^ 4 x d x+ ₀^ 4 x d x & = ₀^ 4 x ^2 x d x aligned aligned & Let x=z, d z= ^2 x d x & x ^2 x d x= z d z= z^2 2 +C aligned where C= constant I= [ ^2 x 2 ]₀^ 4 = 1 2 -0= 1 2 .