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If \(\log_{(cos x)}(sin x) + \log_{(sin x)}(cos x) = 2,\) then the value of \(x\) is

Question and options

If log⁡(cosx)(sinx)+log⁡(sinx)(cosx)=2,\log_{(cos x)}(sin x) + \log_{(sin x)}(cos x) = 2, then the value of xx is
  1. nπ+π4,nn\pi + \dfrac{\pi}{4}, n is an integer
  2. 2nπ+π4,n2n\pi + \dfrac{\pi}{4}, n is an integer
  3. nπ4,n \dfrac{n\pi}{4}, n is an integer
  4. nπ4+π4,n\dfrac{n\pi}{4} + \dfrac{\pi}{4}, n is an integer

Answer and explanation

Correct answer: B - \(2n\pi + \dfrac{\pi}{4}, n\) is an integer
With t = log_cos(sin x), t+1/t=2 gives t=1, so sin x = cos x, with both positive and not 1 (valid log bases/arguments). So x is in the first quadrant: x = 2n pi + pi/4 (n pi + pi/4 with odd n gives negative sin and cos).

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