Question

Plzzz solv it fast no. v in the following image

Answer 1

( x² + y² -z² )² -4x²y²

= (x² + y² -z² -2xy)(x² + y² -z² +2xy)

={(x -y)² -z² } {( x +y)² - z² }

= { (x -y -z)(x -y +z ) } { (x + y+ z )(x + y -z ) }