Question

If a-b = -8, ab = -12, then find a3-b3.

Answer 1

a-b= -8

On sq both sides
asq + bsq -2ab= 64
asq + bsq +24= 64
asq + bsq= 40

Now acube - bcube= (a-b)(asq + bsq +ab)

= (-8)(40-12)
= (-8)(28)
= -224 Ans