Question

Rút gọn: \(S=\frac{2a+2ab-b-1}{3b\left(2a-1\right)+6a-3}\) \(\left(a,b\in Q;a\ne\frac{1}{2};b\ne1\right)\)

Answer 1

\(S=\frac{2a+2ab-b-1}{3b\left(2a-1\right)+6a-3}\\ =\frac{2a\left(b+1\right)-\left(b+1\right)}{3b\left(2a-1\right)+3\left(2a-1\right)}\\ =\frac{\left(2a-1\right)\left(b+1\right)}{3\left(b+1\right)\left(2a-1\right)}\\=\frac{1}{3}\)