ABC is an isosceles triangle, right angled at C. Prove that AB²=2AC²

In ΔABC, By Pythagoras Theorem, (AB)²=(AC)²+(BC)² (1) Since, ΔABC is an isosceles triangle, ∴AC=BC (2) ∴From (1) and (2), (AB)²=2(AC)² [hence proved]