Question

find the value off a³-b³, if a -b=8 and ab=12​

Answer 1

Answer:

8³-12³=64×8-144×12=4416

Answer 2

Answer:

(a - b)3 =a3 - b3 - 3ab (a - b )

a - b = -8, ab = - 12

a3 - b3 = (a - b)3 + 3ab (a - b )

= ( -8)3 + 3 ( -12 ) ( -8 ) = - 224