Answer:
The least common denominator is (b-8)(b+8)(b-1)
Step-by-step explanation:
We are given expression as
[tex]\frac{b}{b^2-64}-\frac{7b}{b^2+7b-8}[/tex]
Firstly, we will factor both denominators
[tex]b^2-64=b^2-8^2=(b-8)(b+8)[/tex]
[tex]b^2+7b-8=(b+8)(b-1)[/tex]
so, we can plug it back
[tex]\frac{b}{(b-8)(b+8)}-\frac{7b}{(b+8)(b-1)}[/tex]
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
[tex]LCD=(x-8)(x+8)(x-1)[/tex]
