Evaluate `int_(0)^(infty) e^(-x^2/4)dx`

Evaluate int_(0)^(infty) e^(-x)x^(3)dx .

Evaluate :int_(0)^(oo)e^(-x)dx

Evaluate int_(0)^(1)e^(2-3x)dx

Evaluate int_(0)^(1)e^(2-3x)dx

Evaluate : int_0^(ln2)x e^(-x)dx

The value of int_(0)^(infty)[2e^(-x)] dx (where ,[.] denotes the greatest integer function of x) is equal to S

Evaluate int_(0)^(2)e^(x)dx