Question

Using a suitable identity find a) 97times 103 (b) (3a-4b)^(3)​

Answer 1

Step-by-step explanation:

(a). (100-3)(100+3)

by using identity (a-b)(a+b)=(a^2-b^2)

therefore,

= (100^2-3^2)

=10000-9

=9991

(b). using identity (a-b)^3=a^3-b^3-3ab(a-b)

=3a^3-4b^3-3(3a)(4b)(3a-4b)

=27a^3-64b^3-36ab(3a-4b)

=27a^3-64b^3-108a^2b+144ab^2

I hope you will understand