Simplifying-Surds Edexcel Higher

Surds & exact values

What is a surd?

• A surd is the square root of a non-square integer

• Using surds lets you leave answers in exact form

  • e.g.  rather than 

How do I do calculations with surds?

•  Multiplying surds

  • You can multiply numbers under square roots together

  • 

• Dividing surds

  • You can divide numbers under square roots

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