Question 59

If a - b = 5 and ab = 6, then $$(a^3 - b^3)$$ is equal to:

Solution

a - b = 5

$$(a - b)^2 = a^2 + b^2 - 2ab = 25$$

$$a^2 + b^2$$=37

$$a^3 - b^3=(a -b) (a^2 +ab +b^2)$$

=>$$5 \times (37 + 6)$$ = 215

So , the answer would be option d)215.

Share on Whatsapp Share on Whatsapp

Create a FREE account and get:

Free SSC Study Material - 18000 Questions
230+ SSC previous papers with solutions PDF
100+ SSC Online Tests for Free

Follow us on

Boost your Prep!

Download App