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Question
If `"m" -1/"m"=5`, find: `"m"^2-1/"m"^2`
Sum
Solution
`"m"^2-1/"m"^2=("m"+1/"m")("m"-1/"m")`
`=5("m"+1/"m")`
Now `("m"+1/"m")^2=("m"-1/"m")^2+4`
= (5)2 + 4
= 25 + 4
= 29
`∴"m"+1/"m"=sqrt29`
`∴"m"^2-1/"m"^2=(5)(sqrt29)=5sqrt29`
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