Q.

Let f(x)=(2-x2).ex(1+x)(1-x)3/2dx. If f(0)=0, then f(12) is equal to:             [2026]

1 3e+1  
2 2e-1  
3 2e+1  
4 3e-1  

Ans.

(4)

ex((1-x2)+11+x.(1-x)3/2)dx

=ex((1-x2)1+x.(1-x)3/2+11+x.(1-x)3/2)dx

=ex(1+x1-x+11+x.(1-x)3/2)dx

=ex1+x1-x+C

f(x)=ex1+x1-x-1

f(12)=3e-1