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Question
Simplify the following expressions:
`(sqrt8 - sqrt2)(sqrt8 + sqrt2)`
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Solution
We know that `(a - b)(a + b) = a^2 - b^2`. We will use this porperty to simplify the expression
`(sqrt8 - sqrt2)(sqrt8 + sqrt2)`
`∴(sqrt8 - sqrt2)(sqrt8 + sqrt2) = (sqrt8)^2 - (sqrt2)^2`
`= sqrt8 xx sqrt8 - sqrt2 xx sqrt2`
`= (8^2)^(1/2) - (2^2)^(1/2)`
`=8^1 - 2^1`
= 6
Hence the value of expression is 6
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