Question

Evaluate using identity
93³-107³

Answer 1

Hi friend!!

Given,

93³-107³

=(100-7)³-(100+7)³

Consider,

(a-b)³-(a+b)³

=a³-3a²b+3ab²-b³-(a³+b³+3a²b+3ab²)

=-6a²b-2b³

=-2b(3a²-b²)

Let a=100,b=7

=-2(7)(3(10⁴)-49)

=-14(2951)

=-41314

I hope this will help you ;)

Answer 2

Answer:-420686

using the identity [(a-b)³-(a+b)³]

=2(b³+3a²b)

93³ - 107³

=(100-7)³ - (100+7)³

=2{(7)³-3.(100)².7}

=2{343-210000}

=2(-210343)=

-420686