If a+b = 10 and a2 + b2 = 58 find the value of a3 + b3 - Maths - Polynomials

Question

If a+b = 10 and a2 + b2 = 58 find the
value of a3 + b3

Abhinav Verma · Accepted Answer

( a + b)2 = a2 + b2 + 2ab
100 = 58 + 2ab
42 = 2ab
ab = 21
(a + b)3 = a3 + b3 + 3ab(a +
b)
1000 = a3 +b3 + 3*21(10)
1000 = a3 +b3 + 630
a3 +b3 = 370