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प्रश्न
`1/((1+ sintheta ))+1/((1- sin theta ))= 2 sec^2 theta`
उत्तर
LHS =`1/((1+ sin theta)) + 1/((1-sin theta))`
=` ((1- sin theta )+ (1+ sin theta))/((1+ sin theta) (1- sintheta))`
= `2/(1- sin^2 theta)`
= `2/ (cos^2 theta )`
= `2 sec^2 theta`
= RHS
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