Question

Find the multiplicative inverse of (–7)^–2 ÷ (90)^–1.

Answer 1

As we know that a is called multiplicative inverse of b, If a × b = 1.

Given:

(–7)^–2 ÷ (90)^–1 

Simplify the above expression as follows:

`(-7)^-2 ÷ (90)^-1 = 1/(7)^2 ÷ 1/(90)^1`

= `1/49 ÷ 1/90`

= `1/49 xx 90/1`

= `90/49` 

Let `b = 90/49`

So, `a xx 90/49 = 1`

`a = 49/90`

Hence, the multiplicative inverse is `49/90`.