Question

Find the mistake in the given equation when it is given that a=b adding a on both sides, it becomes a^2=ab....... Now subtracting b^2 from both sides it becomes a^2-b^2=ab-b^2........Now factorising it becomes (a+b)(a-b)=b(a-b)...........Cancel a-b on both sides, it becomes a+b=b.... As a=b (given) .......a+a=a.......2à=a........which proves 2=1 !!!!!!

Answer 1

if a=b. when it is added by a on both sides it becomes 2a=b+a and not a^2=ab so that is one minor mistake behind this equation. so then 2a=a+b

a+a=a+b
a+a-a=b
a=b or 0=0. so therefore 1≠2.