Surds (maths revision) Higher

A surd is a squre root which cannot be reduce to a whole number. For example, 4 sqpare roots = 2 is not a surd, because the answer is a wholel number. But 5 square roots is not a whole number. You could use a calcultor to find out the square roots of 5 is 2.236067977.. but instead of this we leave the answers in the square root form, as a surd.

You'll need to be able to simplify expressions involving surds. Here are some genaral rules.

Simplifly the squre root of 12

• use the general rules

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•   

Simplify

• use the general rules
• 

• = = = 6

Simplify

• use general rules

• =