Question

Verify: (1) x^3+y^3=(x+y) (x^2-xy+y^2)​

Answer 1

Multiple the terms which is in the right hand side

and cancel the terms which will be cancel

$x( {x}^{2} - xy + {y}^{2} ) + y( {x}^{2} - xy + {y}^{2}) \\ {x}^{3} - {x}^{2} y + x {y}^{2} + {x}^{2} y - x {y}^{2} + {y}^{3} \\ {x}^{3} + {y}^{3}$