Q19 of 32 Page 2

Evaluate (99)3.

Concept Used:


(a – b)3 = a3 – b3 – 3ab(a – b)


Explanation:


(99)3 = (100 – 1)3


(99)3 = (100)3 – (1)3 – 3.100.1(100 – 1)


(99)3 = 1000000 – 1 – 300 × 99


(99)3 = 1000000 – 29701


(99)3 = 970299.


More from this chapter

All 32 →
17

Factorize: 27x3 + y3 + z3 – 9xyz

 18

If , find the value of .

 20

Without actually calculating the cubes, find the value of

(–12)3 + (7)3 + (5)3.

 21

Verify:

(i) x3 + y3 = (x + y) (x2 + y2 – xy)


(ii) x3 – y3 = (x – y) (x2 + y2 + xy)