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प्रश्न
Given `cos38^circ sec(90^circ - 2A) = 1` , Find the value of <A
उत्तर
`cos38^circ sec(90^circ - 2A) = 1`
⇒ `cos38^circcosec2A = 1`
⇒ `cos38^circ (1/(sin2A)) = 1`
⇒ `sin2A = cos(90 - 52^circ)`
⇒ `sin2A = sin52^circ`
⇒ `2A = 52^circ`
⇒ `A = 26^circ`
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