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Prove that`(cos10^0+sin10^0)/(cos10^0-sin 10^0)=tan55^0`

Answer» `L.H.S. = (cos10^@ + sin10^@)/(cos10^@ - sin10^@)`
`=(cos10^@(1+tan10^@))/(cos10^@(1-tan10^@))`
`=(1+tan10^@)/(1-tan10^@)`
`=(tan45^@+tan10^@)/(1-tan45^@tan10^@)`
`=tan(45^@+10^@)`
`=tan55^@ = R.H.S.`


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