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प्रश्न
Without using trigonometric tables, evaluate :
`tan 27^circ/cot 63^circ`
उत्तर
`tan 27^circ/cot 63^circ`
= `tan (90^circ - 63^circ)/cot 63^circ`
= `cot 63^circ/cot 63^circ` [`because` tan (90-θ) = cot θ]
= 1
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