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.


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