If x-y = 5 and xy =84, then find the value of x cube - y cube - Maths - Polynomials

Question

If x-y = 5 and xy =84, then find the value of x cube - y
cube

Manbar Singh · Accepted Answer

We know that,      x-y3 = x3 - y3 - 3xyx - y⇒x3 - y3 = x-y3  + 3xyx-y⇒x3 - y3 = 53  + 3845⇒x3 - y3 = 125 + 1260 = 1385