How do I simplify a surd?

To simplify a surd, remember that

sqrt(a*b) = sqrt(a)*sqrt(b)

If either a or b are square numbers, you can simply write its square root. Hence, to simplify a surd, you must look for any factors of the number inside the square root that are sqaure numbers.

For example, 

sqrt(20) = sqrt(4*5) = sqrt(4)*sqrt(5)

sqrt(4) = 2 therefore sqrt(20) = 2sqrt(5)

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