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Solve the equation: 1 + 2 cosecx = -(sec...

Solve the equation: `1 + 2 cosecx = -(sec^2 (x/2))/2`

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To solve the equation \( 1 + 2 \csc x = -\frac{\sec^2 \left( \frac{x}{2} \right)}{2} \), we will follow these steps: ### Step 1: Rewrite the equation We start with the given equation: \[ 1 + 2 \csc x = -\frac{\sec^2 \left( \frac{x}{2} \right)}{2} \] We can rewrite \(\csc x\) and \(\sec^2 \left( \frac{x}{2} \right)\) in terms of sine and cosine: \[ \csc x = \frac{1}{\sin x} \quad \text{and} \quad \sec^2 \left( \frac{x}{2} \right) = \frac{1}{\cos^2 \left( \frac{x}{2} \right)} \] Thus, the equation becomes: \[ 1 + \frac{2}{\sin x} = -\frac{1}{2 \cos^2 \left( \frac{x}{2} \right)} \] ### Step 2: Clear the fractions To eliminate the fractions, we can multiply through by \(2 \sin x \cos^2 \left( \frac{x}{2} \right)\): \[ 2 \sin x \cos^2 \left( \frac{x}{2} \right) + 4 \cos^2 \left( \frac{x}{2} \right) = -\sin x \] ### Step 3: Rearrange the equation Rearranging gives: \[ 2 \sin x \cos^2 \left( \frac{x}{2} \right) + \sin x + 4 \cos^2 \left( \frac{x}{2} \right) = 0 \] Factoring out \(\sin x\): \[ \sin x (2 \cos^2 \left( \frac{x}{2} \right) + 1) + 4 \cos^2 \left( \frac{x}{2} \right) = 0 \] ### Step 4: Set factors to zero This gives us two cases to consider: 1. \(\sin x = 0\) 2. \(2 \cos^2 \left( \frac{x}{2} \right) + 1 + 4 \cos^2 \left( \frac{x}{2} \right) = 0\) ### Step 5: Solve \(\sin x = 0\) The solutions for \(\sin x = 0\) are: \[ x = n\pi \quad (n \in \mathbb{Z}) \] ### Step 6: Solve the second equation For the second case: \[ 6 \cos^2 \left( \frac{x}{2} \right) + 1 = 0 \] This implies: \[ \cos^2 \left( \frac{x}{2} \right) = -\frac{1}{6} \] Since \(\cos^2\) cannot be negative, there are no solutions from this case. ### Final Solution Thus, the only solutions to the original equation are: \[ x = n\pi \quad (n \in \mathbb{Z}) \] ---
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