Question

if X + Y equal to A and X square + Y square equal to b then the value of x cube + y cube

Answer 1

x + y = A

(x + y) ² = A²

x² + y² + 2xy = A²

B + 2xy = A²

2xy = A² - B

xy = A²-B/2

Now.

x³ + y³ = ( x + y) ( x² -xy + y² )

x³ + y³ = ( A) [ B - ( A²- B) /2 ]

= A [ 2B - A² + B ] / 2

= A [ 3B - A²] /2

= 3AB - A³ / 2

Answer 2

see in attachment..................