Find the values of a if `x^(2)-2(a-1) x +(2a+1)=0` have positive roots.

If alpha and alpha^(2) are the roots of the equation x^(2) - 6x + c = 0 , then the positive value of c is

Find the value of int_(0)^(1)3sqrt(2x^(3)-3x^(2)-x+1)dx .