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Verify : "cosec "alpha=1+cot^(2)alpha"...

Verify :
`"cosec "alpha=1+cot^(2)alpha" if "alpha=(pi)/(3)`.

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To verify the identity \( \csc \alpha = 1 + \cot^2 \alpha \) for \( \alpha = \frac{\pi}{3} \), we will follow these steps: ### Step 1: Calculate \( \csc \left( \frac{\pi}{3} \right) \) The cosecant function is the reciprocal of the sine function. Therefore, \[ \csc \left( \frac{\pi}{3} \right) = \frac{1}{\sin \left( \frac{\pi}{3} \right)} \] We know that \( \sin \left( \frac{\pi}{3} \right) = \frac{\sqrt{3}}{2} \). Thus, \[ \csc \left( \frac{\pi}{3} \right) = \frac{1}{\frac{\sqrt{3}}{2}} = \frac{2}{\sqrt{3}} \] ### Step 2: Calculate \( \cot \left( \frac{\pi}{3} \right) \) The cotangent function is the reciprocal of the tangent function. Therefore, \[ \cot \left( \frac{\pi}{3} \right) = \frac{1}{\tan \left( \frac{\pi}{3} \right)} \] We know that \( \tan \left( \frac{\pi}{3} \right) = \sqrt{3} \). Thus, \[ \cot \left( \frac{\pi}{3} \right) = \frac{1}{\sqrt{3}} \] ### Step 3: Calculate \( \cot^2 \left( \frac{\pi}{3} \right) \) Now we will square the value of \( \cot \left( \frac{\pi}{3} \right) \): \[ \cot^2 \left( \frac{\pi}{3} \right) = \left( \frac{1}{\sqrt{3}} \right)^2 = \frac{1}{3} \] ### Step 4: Calculate \( 1 + \cot^2 \left( \frac{\pi}{3} \right) \) Now we will add 1 to \( \cot^2 \left( \frac{\pi}{3} \right) \): \[ 1 + \cot^2 \left( \frac{\pi}{3} \right) = 1 + \frac{1}{3} = \frac{3}{3} + \frac{1}{3} = \frac{4}{3} \] ### Step 5: Compare \( \csc \left( \frac{\pi}{3} \right) \) and \( 1 + \cot^2 \left( \frac{\pi}{3} \right) \) Now we will compare the two results: \[ \csc \left( \frac{\pi}{3} \right) = \frac{2}{\sqrt{3}} \] and \[ 1 + \cot^2 \left( \frac{\pi}{3} \right) = \frac{4}{3} \] To compare these, we can convert \( \frac{2}{\sqrt{3}} \) to have a common denominator: \[ \frac{2}{\sqrt{3}} = \frac{2 \cdot \sqrt{3}}{3} = \frac{2\sqrt{3}}{3} \] Now we need to check if \( \frac{2\sqrt{3}}{3} = \frac{4}{3} \). ### Step 6: Verify the equality To verify the equality, we can square both sides: \[ \left( \frac{2\sqrt{3}}{3} \right)^2 = \left( \frac{4}{3} \right)^2 \] Calculating both sides: \[ \frac{4 \cdot 3}{9} = \frac{16}{9} \] Since both sides are equal, we conclude that: \[ \csc \left( \frac{\pi}{3} \right) = 1 + \cot^2 \left( \frac{\pi}{3} \right) \] Thus, the identity is verified.
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