Question

Find the value of
a^3 + b^3 - 12ab + 64 when a + b = – 4​

Answer 1

Answer:

0

Step-by-step explanation:

a³+b³- 12ab +64 is given and a+b= - 4

Also we can write the expression as

[a³+b³+3 ab(a+b)] - 3 ab(a+b) - 12ab +64.

{Hear a³+b³-3ab(a+b) is in the form (a+b) ³}

Then

(a+b) ³-3ab(a+b) - 12ab +64_________(1)

Now substute a+b = -4 in the equation (1)

(-4)³ - 3ab (-4) - 12ab +64

-64 +12ab - 12ab +64 =>0

Therefor a³+b³ - 12ab +64 =0