Question

prove that [x+y]3 - [x-y]3 -6y [x2-y2]=8y3

Answer 1

Step-by-step explanation:

formulas :

${(x + y)}^{3} = {x}^{3} + {y}^{3} + 3 {x}^{2} y + 3x {y}^{2}$

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