If $a - b = 4, a^{2} + b^{2} + a b = 8, t h e n a^{3} - b^{3} = ?$

32

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244

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240

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Solution

The correct option is B $32$
Solution:- (A) 32
As we know that,
$a^{3} - b^{3} = (a - b) (a^{2} + a b + b^{2})$
Given:-
$a - b = 4$
$a^{2} + b^{2} + a b = 8$
$∴ a^{3} - b^{3} = 4 \times 8 = 32$
Hence, the correct answer is 32.

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If a−b=4,a2+b2+ab=8,thena3−b3=?

The correct option is B 32Solution:- (A) 32As we know that,a3−b3=(a−b)(a2+ab+b2)Given:-a−b=4a2+b2+ab=8∴a3−b3=4×8=32Hence, the correct answer is 32.

If $a - b = 4, a^{2} + b^{2} + a b = 8, t h e n a^{3} - b^{3} = ?$

The correct option is B $32$
Solution:- (A) 32
As we know that,
$a^{3} - b^{3} = (a - b) (a^{2} + a b + b^{2})$
Given:-
$a - b = 4$
$a^{2} + b^{2} + a b = 8$
$∴ a^{3} - b^{3} = 4 \times 8 = 32$
Hence, the correct answer is 32.