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Two numbers a and $b$ satisfy $a - b = 2$ and $ab = 15$ . Find $a^{3} - b^{3}$ .

Class 9Algebraic IdentitiesPolynomials

A−82
B8
C98
D38

Step-by-Step Solution

a^{3} - b^{3} = (a - b)^{3} + 3 ab (a - b) = 8 + 90 = 98

. Check:

a = 5, b = 3

gives 125 − 27 = 98.

Answer: C) 98

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