Question

proved that (a-b)^3=a^3-b^3-3ab(a-b).​

Answer 1

To prove :

(a - b) ³ = a³ - b³ - 3ab (a - b)

Proof :

LHS =

(a - b) ³

=)) (a - b) (a - b) (a - b)

=)) ( a² - ab -ab + b² ) (a - b)

=)) a³ -a²b -a²b + ab² -a²b + ab² +ab² - b³

=)) a³ - a²b -a²b - a²b + ab² + ab² + ab² - b³

=)) a³ - 3a²b + 3ab² - b³

=)) a³ - b³ -3ab (a - b)

= RHS

hence proved

Answer 2

Your Answer is here .