How to Rationalize the Numerator in a Fraction?

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To rationalize the numerator of the fraction (√x - 3) / (x - 9), the correct approach involves multiplying both the numerator and denominator by the conjugate of the numerator, which is (√x + 3). This leads to the expression (x - 9) / (x√x + 3x - 9√x - 27). By factoring the denominator and canceling common factors, the expression simplifies to 1 / (√x - 3). The final result confirms the textbook's answer, demonstrating the successful rationalization of the numerator.
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1.
Haven't done this type of math in a long time, here's the question:
1. Rationalize the numerator
a) (√x - 3) / (x - 9)


Can't get the answer for the life of me. The textbook says (1)/(√x - 3)

the / dictates division.




2. Homework Equations
Question: (√x - 3) / (x - 9)
Answer: (1)/(√x - 3)




3. The Attempt at a Solution

I multiplied the top and bottom by the conjugate of the numerator (√x + 3)
and ended up getting (x-9)/(x√x + 3x - 9√x - 27)

and I get stumped here.
 
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Instead of multiplying the denominator out like that, leave it factored and see if you can cancel factors.
 
From here, which looks good, (x-9)/(x√x + 3x - 9√x - 27)
= \frac{x-9}{\sqrt{x}(x-9)+3(x-9}
= \frac{x-9}{(x-9)(\sqrt{x}-3)}
... can then be simplified.
 
Alright, I got it guys!
Thanks :)
 
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