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If a-b=-8\ \ a n d\ \ a b=-12 , then a^3...

If `a-b=-8\ \ a n d\ \ a b=-12 ,` then `a^3-b^3=?` (a)`-244` (b) `-240` (c) `-224` (d) `-260`

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`a^3 - b^3 `
`= (a – b)^3 + 3ab (a- b)`
`= ( -8 )^3 + 3 (-12) (-8)`
`= -512 + 288`
` = -224`
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