Question 56

If a + b = 8 and ab = $$\frac{32}{3}$$, then $$(a^3 + b^3)$$ is equal to:

Solution

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

$$8^ 3 $$ = $$ a^3 + b^3 + 3 \times \frac{32}{3}\times 8 $$

512 = $$a^3$$ + $$b^3$$ + 256

$$a^3$$ + $$b^3$$ =256

Share on Whatsapp Share on Whatsapp

Create a FREE account and get: