Rationalize the denominator.
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Hello and Good Morning/Afternoon!
Let's take this problem step-by-step:
What the problem asks for:
⇒ to rationalize the denominator
⇒ rationalize means that you multiply the numerator and
demonimator by the denominator
Let's put that into action:
[tex]\frac{\sqrt{a +1}-2 }{\sqrt{a+1}+2 } * \frac{\sqrt{a +1}+2 }{\sqrt{a+1}+2 }\\=\frac{a +1-4 }{a+1+4\sqrt{a+1}+4 } \\=\frac{a-3}{a+4\sqrt{a+1}+5 }[/tex]<== Answer
Hopefully that helps!