Question

a-b=4,ab=21find a3_b3

Answer 1

a3-b3=(a-b) (a^2+b^2+ab)

= 4(a^2+b^2+2)
=4[(a-b) ^2+ab+2)
=4[16+2+2]
=4*20
= 80❤ hope it helps please mark me as Brainlist ❤

Answer 2

a3-b3=(a-b)^3+3ab(a-b)
=4^3+3×2×4
=64+24
=88
the answer is 88