Rationalize the denominator and simplify.

Question

ZombieLover · Answer

attachment

AZ · Answer

Same idea as last time. What's the conjugate?

AZ · Answer

What's the conjugate of $\color{red}{\sqrt{a+1}} + \color{green}{2}$

the conjugate of a+b is a-b

ZombieLover · Answer

$$\sqrt{a-1}-2$$

AZ · Answer

Good, now multiply the numerator and denominator by it.

And don't forget this formula:
(a+b)(a-b) = a^2 - b^2

ZombieLover · Answer

which is the Numerator and denominator? what numbers?

yaboiaction · Answer

why just why

ZombieLover · Answer

$\color{#0cbb34}{\text{Originally Posted by}}$ @yaboiaction
why just why
$\color{#0cbb34}{\text{End of Quote}}$

what?

AZ · Answer

numerator and denominator of your question with the conjugate

$\dfrac{\sqrt{a+1}-2}{\sqrt{a+1}+2 }\times \dfrac{\sqrt{a+1}-2}{\sqrt{a+1}-2}$

ZombieLover · Answer

ohhh ok thank you

AZ · Answer

remember $\sqrt{a+1}$ is one term, we don't change the sign inside it