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Prove that: (1+sintheta-costheta)/(1+sin...

Prove that: `(1+sintheta-costheta)/(1+sintheta+costheta)=tan(theta/2)`

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`sin theta=frac{2 tan frac{theta}{2}}{1+tan ^{2} frac{theta}{2}}`

`cos theta=frac{1-tan ^{2} frac{theta}{2}}{1+tan ^{2} frac{theta}{2}}`

Substituting this in the above equation we get, `frac{1+tan ^{2} frac{theta}{2}+2 tan frac{theta}{2}-1+tan ^{2} frac{theta}{2}}{1+tan ^{2} frac{theta}{2}+2 tan frac{theta}{2}+1-tan ^{2} frac{theta}{2}}`

`Rightarrow frac{2 tan frac{theta}{2}+2 tan ^{2} frac{theta}{2}}{2+2 tan frac{theta}{2}}=tan frac{theta}{2}`

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