> a = 1 > b = 1 > a = b > ab = b^2 > ab - a^2 = b^2 - a^2 > a(b - a) = (b + a)(b - a) [factor] > a = b + a > 1 = 2 > > Right?
Wrong. On the factor line you divided both sides of the equation by (b-a). Early you stated a = 1 and b = 1 so (b-a) = 0. You cannot divide both sides of the equation by 0. You were correct up to that point though. That was a tricky proof. Some people in this forum will not be able to solve it.