Question

factorise:- x^2-y^2-2y-1

Answer 1

(x+y+1)(x -y -1) this is required factorisation.

Answer 2

Given Equation is x^2 - y^2 - 2y - 1

                             = x^2 - (y + 1)^2

We know that a^2 - b^2 = (a+b)(a-b)

                             = (x + (y + 1))(x - (y + 1)

                             = (x + y + 1)(x - y - 1).


Hope this helps!