Question

Find the least common denominator for these two rational expressions. B/b^2 -64 -7b/b^2+7b-8

Answer 1

Answer:

The least common denominator is (b-8)(b+8)(b-1)

Step-by-step explanation:

We are given expression as

$\frac{b}{b^2-64}-\frac{7b}{b^2+7b-8}$

Firstly, we will factor both denominators

$b^2-64=b^2-8^2=(b-8)(b+8)$

$b^2+7b-8=(b+8)(b-1)$

so, we can plug it back

$\frac{b}{(b-8)(b+8)}-\frac{7b}{(b+8)(b-1)}$

First term denominator is

(b-8)(b+8)

Second term denominator is

(b+8)(b-1)

So,

Least common denominator will be

(b-8)(b+8)(b-1)

So, we get

$LCD=(x-8)(x+8)(x-1)$