 Hello and welcome to the session. Let us understand the following question today. A B C is an isosceles triangle right angle. Let's see. Prove that A B squared is equal to twice of A C squared. Now, before starting with the solution, let us understand what is the Pythagoras theorem. According to Pythagoras theorem in a right angle triangle, the square of the hypotenuse is equal to the sum of the squares of the other two sides. This is the key idea to our question. Now, let us write the solution. Let us first see the figure for our question. Here we have triangle A B C which is right angle at C, which is an isosceles triangle where A C is equal to B C. So, by Pythagoras theorem on triangle A B C, we can write which implies A B squared, that is the hypotenuse, is equal to A C squared plus B C squared. But B C is equal to A C given as triangle A B C is an isosceles triangle. So, it implies A B squared is equal to A C squared plus A C squared, which implies A B squared is equal to twice of A C squared. And this is our required result. Hence, proved. I hope you understood the question. Bye and have a nice day.