Given:
The functions are:
[tex]p(x)=\dfrac{1}{x+1}[/tex]
[tex]q(x)=\dfrac{1}{x-1}[/tex]
To find:
The rational expression for [tex]p(x)-q(x)[/tex].
Solution:
We have,
[tex]p(x)=\dfrac{1}{x+1}[/tex]
[tex]q(x)=\dfrac{1}{x-1}[/tex]
Now,
[tex]p(x)-q(x)=\dfrac{1}{x+1}-\dfrac{1}{x-1}[/tex]
[tex]p(x)-q(x)=\dfrac{(x-1)-(x+1)}{(x+1)(x-1)}[/tex]
[tex]p(x)-q(x)=\dfrac{x-1-x-1}{x^2-1^2}[/tex] [tex][\because a^2-b^2=(a-b)(a+b)][/tex]
[tex]p(x)-q(x)=\dfrac{-2}{x^2-1}[/tex]
Therefore, the required rational expression for [tex]p(x)-q(x)[/tex] is [tex]\dfrac{-2}{x^2-1}[/tex].