The least integral value of ‘a’ for which the equation x2−2(a−1) x +(2a+1)=0 has both the roots positive is

If two roots are positive  a,b are of different sign and △⩾0 Δ≥0 and coeff of x<0 ⇒4(a−1)2−4(2a+1)≥0 ;               −2(a−1)<0⇒a2−4a≥0                                          ⇒a−1>0    a≤0 or a≥4                                                ⇒a>1