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Write a factor that you can use to rationalize the denominator of $\frac{\sqrt{2}}{\sqrt{5}-8}$

Write a factor that you can use to rationalize the denominator of $\frac{\sqrt{2}}{\sqrt-example-1

2 Answers

10 votes

Answer:


√(5)+8

Explanation:

To rationalize the denominator, you would need to multiply the numerator and denominator by its conjugate. The conjugate of
√(5)-8 is
√(5)+8, so, if you wanted to do the actual math:


\displaystyle (√(2))/(√(5)-8)\\ \\(√(2))/(√(5)-8)\cdot(√(5)+8)/(√(5)+8)\\ \\(√(10)+8√(2))/(5-64)\\ \\(√(10)+8√(2))/(-59)\\ \\(√(10)-8√(2))/(59)

This method works because
(√(5)-8)(√(5)+8)=(√(5)^2-8^2), which is a difference of squares, and helps to eliminate the radicals in the denominator.

Hope this helps!

7 votes
hello.

The rationalizing factor of it is root 2/root 5+8

We must multiply both numerator and denominator by it.
User Dmehro
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