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The solution of the equation "log"("co...

The solution of the equation
`"log"_("cos"x) "sin" x + "log"_("sin"x) "cos" x = 2` is given by

A

`x = n pi + (pi)/(4), n in Z`

B

`x = n pi + (pi)/(2), n in Z`

C

`x = n pi + (pi)/(8), n in Z`

D

`x = 2n pi + (pi)/(6), n in Z`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equation \[ \log_{\cos x} \sin x + \log_{\sin x} \cos x = 2, \] we will follow these steps: ### Step 1: Apply the Change of Base Formula Using the property of logarithms, we can rewrite the logarithms in terms of natural logarithms: \[ \log_{\cos x} \sin x = \frac{\log \sin x}{\log \cos x} \] and \[ \log_{\sin x} \cos x = \frac{\log \cos x}{\log \sin x}. \] Thus, the equation becomes: \[ \frac{\log \sin x}{\log \cos x} + \frac{\log \cos x}{\log \sin x} = 2. \] ### Step 2: Combine the Terms Next, we find a common denominator for the left-hand side: \[ \frac{(\log \sin x)^2 + (\log \cos x)^2}{\log \sin x \cdot \log \cos x} = 2. \] ### Step 3: Cross-Multiply Cross-multiplying gives us: \[ (\log \sin x)^2 + (\log \cos x)^2 = 2 \log \sin x \cdot \log \cos x. \] ### Step 4: Rearranging the Equation Rearranging the equation, we have: \[ (\log \sin x)^2 - 2 \log \sin x \cdot \log \cos x + (\log \cos x)^2 = 0. \] ### Step 5: Recognize the Perfect Square This can be recognized as a perfect square: \[ (\log \sin x - \log \cos x)^2 = 0. \] ### Step 6: Solve the Perfect Square Taking the square root of both sides gives: \[ \log \sin x - \log \cos x = 0. \] This implies: \[ \log \sin x = \log \cos x. \] ### Step 7: Exponentiate Both Sides Exponentiating both sides leads to: \[ \frac{\sin x}{\cos x} = 1, \] which means: \[ \tan x = 1. \] ### Step 8: General Solution for Tangent The general solution for \( \tan x = 1 \) is: \[ x = n\pi + \frac{\pi}{4}, \quad n \in \mathbb{Z}. \] ### Final Answer Thus, the solution of the equation is: \[ x = n\pi + \frac{\pi}{4}, \quad n \in \mathbb{Z}. \] ---
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OBJECTIVE RD SHARMA ENGLISH-TRIGONOMETRIC EQUATIONS AND INEQUATIONS-Chapter Test
  1. The set of values of x in (-pi, pi) satisfying the inequation |4"sin" ...

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  2. If theta in [0, 5pi] and r in R such that 2 sin theta = r^(4) -2r^(2) ...

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  3. If rsintheta=3, r=4(1+sintheta) where 0<=theta<=2pi then theta e...

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  4. The solution set of the inequation "log"(1//2) "sin" x gt "log"(1//...

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  5. If the equation "sin" theta ("sin" theta + 2 "cos" theta) = a has a re...

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  6. The equation "sin"^(4) theta + "cos"^(4) theta = a has a real solution...

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  7. If 32"tan"^(8)theta" = 2"cos"^(2) alpha- 3"cos" alpha " and "3"cos" 2 ...

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  8. The general value of theta satisfying tantheta tan(120^@-theta) tan(12...

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  9. The solution of the equation "log"("cos"x) "sin" x + "log"("sin"x) "...

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  10. The number of solutions of the equation tanx+secx=2cosx lying in the i...

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  11. One root of the equation "cos" theta-theta + (1)/(2) = 0 lies in the i...

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  12. If "sin" (pi "cos" theta) = "cos" (pi "sin" theta), then which one fo ...

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  13. If "2sec" (2alpha) = "tan" beta + "cot"beta, then one of the value of ...

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  14. The values of k for which the equation sin^4 x+cos^4 x+sin2x+k=0 posse...

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  15. "tan"|x| = |"tan" x|, if

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  16. The number of solution of the equation |sin x|=|cos 3x| in [-2pi,2pi] ...

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  17. If sin x cos x cos 2x = lambda has a solution, then lambda lies in the...

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  18. If "sin "3theta = 4"sin" theta("sin"^(2) x-"sin"^(2)theta), theta ne n...

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  19. If sin 2x cos 2x cos 4x=lambda has a solution then lambda lies in the...

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  20. If the equation cos (lambda "sin" theta) = "sin" (lambda "cos" theta) ...

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