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Question
Simplify the following expression:
`(sqrt5 - sqrt2)(sqrt5 + sqrt2)`
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Solution
The given expression is `(sqrt5 - sqrt2) (sqrt5 + sqrt2)`
We know that (a + b) (a - b) = a2 - b2
⇒ `(sqrt5 - sqrt2) (sqrt5 + sqrt2) = (sqrt5)^2 - (sqrt2)^2`
⇒ `(sqrt5 - sqrt2) (sqrt5 + sqrt2) = 5 - 2`
∴ `(sqrt5 - sqrt2) (sqrt5 + sqrt2) = 3`
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