Question

if a b equal 4 and a + b = 6 then a cube plus b cube is

Answer 1

${(a + b)}^{3} = {a}^{3} + {b}^{3} + 3ab(a + b) \\ 216 = {a}^{3} + {b}^{3} + 3 \times 4 \times 6$
Find a cube plus b cube

Answer 2

(a+b)(a+b)=36
a*a+b*b+2ab=36
a*a+b*b=36-2ab
a*a+b*b=36-2*4
a*a+b*b=28
a*a*a+b*b*b=(a+b)(a*a-ab+b*b)
=6(28-4)
=6*24
=144
Therefore optiond