Question

Si a+b=4 ab= 5 calcular a3+b3

Answer 1

3. 3. 3
(a+b) = a. +3ab+ (a+b)+b
64= a3+b3+15
49=a3+b3

Answer 2

a+b=4            ab=5

(a+b)^3=4^3

a^3+3ab+3ab+b^3=64

a^3+b^3+3ab(a+b)=64

a^3+b^3+3(5)(4)=64

a^3+b^3+60=64

a^3+b^3=64 - 60

a^3+b^3=4