`int_(-oo)^(oo)(dx)/(x^(3))`

Evaluate : (i) int_(-oo)^(oo) (dx)/(x^(2)+2x+2) , (ii) int_(sqrt(2))^(oo)(dx)/(xsqrt(x^(2)-1)) , (iii) int_(0)^(4)(x^(2))/(1+x)dx (iv) int_(0)^(pi//2) sqrt(costheta)sin^(3)theta

int_(1)^(oo)(dx)/(x^(2))

The value of int_(0)^(oo)(dx)/(1+x^(4)) is (a) same as that of int_(0)^(oo)(x^(2)+1dx)/(1+x) (b) (pi)/(2sqrt(2))( c) same as that of int_(0)^(oo)(x^(2)+1dx)/(1+x^(4))(d)(pi)/(sqrt(2))

int_(0)^(oo)(dx)/((1+x^(2))^(4))=

The value of int_(0)^(oo)(dx)/(1+x^(4)) is equal to

If int_(0)^(b)(dx)/(1+x^(2))=int_(b)^( oo)(dx)/(1+x^(2)) , then b=

If I_(1)=int_(0)^(oo) (dx)/(1+x^(4))dx and I_(2)underset(0)overset(oo)int dx"then"n (I_(1))/(I_(2))=

I=int_(-oo)^(1)(1)/(x^(2))dx

I=int_(0)^(oo)(dx)/(1+e^(x))