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प्रश्न
Without using trigonometric tables, evaluate :
`cos 35^circ/sin 55^circ`
उत्तर
`cos 35^circ/sin 55^circ`
= `cos (90^circ - 55^circ)/sin 55^circ`
= `sin 55^circ/sin 55^circ` [`because` sin (90-θ) = cos θ]
= 1
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