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Solve the equation for x and y , |sin x ...

Solve the equation for x and y , `|sin x + cos x|^( sin^(2) x-1//4)=1+|siny| and cos^(2)y=1+sin^(2)y`.

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To solve the equations given in the problem, we will break it down into two parts: solving for \(y\) first, and then solving for \(x\). ### Step 1: Solve the second equation for \(y\) The second equation is: \[ \cos^2 y = 1 + \sin^2 y \] Using the Pythagorean identity, we know that: \[ \cos^2 y + \sin^2 y = 1 \] We can substitute \(\cos^2 y\) from the identity into the equation: \[ 1 - \sin^2 y = 1 + \sin^2 y \] Now, simplifying this gives: \[ - \sin^2 y = \sin^2 y \] Adding \(\sin^2 y\) to both sides results in: \[ 0 = 2\sin^2 y \] This implies: \[ \sin^2 y = 0 \] Taking the square root of both sides, we find: \[ \sin y = 0 \] The general solution for \(\sin y = 0\) is: \[ y = n\pi \quad (n \in \mathbb{Z}) \] ### Step 2: Solve the first equation for \(x\) The first equation is: \[ |\sin x + \cos x|^{\sin^2 x - \frac{1}{4}} = 1 + |\sin y| \] Since we found \(y = n\pi\), we know: \[ \sin y = 0 \quad \Rightarrow \quad 1 + |\sin y| = 1 + 0 = 1 \] Thus, we can rewrite the first equation as: \[ |\sin x + \cos x|^{\sin^2 x - \frac{1}{4}} = 1 \] For the expression to equal 1, we have two cases to consider: 1. **Case 1:** \( |\sin x + \cos x| = 1 \) 2. **Case 2:** \( \sin^2 x - \frac{1}{4} = 0 \) #### Case 1: \( |\sin x + \cos x| = 1 \) This occurs when: \[ \sin x + \cos x = 1 \quad \text{or} \quad \sin x + \cos x = -1 \] For \(\sin x + \cos x = 1\): \[ \sin x + \cos x = \sqrt{2} \sin\left(x + \frac{\pi}{4}\right) = 1 \] This leads to: \[ \sin\left(x + \frac{\pi}{4}\right) = \frac{1}{\sqrt{2}} \quad \Rightarrow \quad x + \frac{\pi}{4} = \frac{\pi}{4} + 2k\pi \quad \text{or} \quad x + \frac{\pi}{4} = \frac{3\pi}{4} + 2k\pi \] Solving gives: \[ x = 2k\pi \quad \text{or} \quad x = \frac{\pi}{2} + 2k\pi \] For \(\sin x + \cos x = -1\): \[ \sin x + \cos x = -\sqrt{2} \sin\left(x + \frac{\pi}{4}\right) = -1 \] This leads to: \[ \sin\left(x + \frac{\pi}{4}\right) = -\frac{1}{\sqrt{2}} \quad \Rightarrow \quad x + \frac{\pi}{4} = \frac{7\pi}{4} + 2k\pi \quad \Rightarrow \quad x = \frac{3\pi}{2} + 2k\pi \] #### Case 2: \( \sin^2 x - \frac{1}{4} = 0 \) This gives: \[ \sin^2 x = \frac{1}{4} \quad \Rightarrow \quad \sin x = \frac{1}{2} \quad \text{or} \quad \sin x = -\frac{1}{2} \] For \(\sin x = \frac{1}{2}\): \[ x = \frac{\pi}{6} + 2k\pi \quad \text{or} \quad x = \frac{5\pi}{6} + 2k\pi \] For \(\sin x = -\frac{1}{2}\): \[ x = \frac{7\pi}{6} + 2k\pi \quad \text{or} \quad x = \frac{11\pi}{6} + 2k\pi \] ### Final Solutions Combining all the solutions for \(x\) and \(y\): - \(y = n\pi\) where \(n \in \mathbb{Z}\) - \(x = 2k\pi\), \(x = \frac{\pi}{2} + 2k\pi\), \(x = \frac{3\pi}{2} + 2k\pi\), \(x = \frac{\pi}{6} + 2k\pi\), \(x = \frac{5\pi}{6} + 2k\pi\), \(x = \frac{7\pi}{6} + 2k\pi\), \(x = \frac{11\pi}{6} + 2k\pi\) where \(k \in \mathbb{Z}\).
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ARIHANT MATHS ENGLISH-TRIGONOMETRIC EQUATIONS AND INEQUATIONS-Exercise (Subjective Type Questions)
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  19. Show that the equation , sec theta + "cosec" theta = c has two roots...

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  20. Solve the equation for x and y , |sin x + cos x|^( sin^(2) x-1//4)=1+|...

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