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प्रश्न
Prove the following:
tan x + cot x = 2 cosec 2x
उत्तर
L.H.S. = tan x + cot x
= `sinx/cosx + cosx/sinx`
= `(sin^2x + cos^2x)/(cosx*sinx)` ...[sin2 + cos2x = 1]
= `1/(sinx*cosx)`
= `2/(2sinx cosx)`
= `2/(sin2x)`
= 2 cosec 2x
= R.H.S.
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