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Question
Prove the following:
`tan(pi/4 + theta) = (1 + tan theta)/(1 - tan theta)`
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Solution
`L.H.S. = tan(pi/4 + theta)`
According to `tan(A + B) = (tan A + tan B) / (1-tan A tan B`,
We get
`L.H.S. = (tan pi/4 + tan theta)/(1 - tan pi/4 tan theta)`
`L.H.S = (1 + tan theta)/(1 -(1) tan theta)` ...[because `tan pi/4 = 1]`
=`(1 + tan theta) / (1 - tan theta)`
Here `L.H.S = R.H.S`, Hence proved
Notes
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