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Evaluate: sin^(2)60^(@) cos^(2)45^(@) co...

Evaluate: `sin^(2)60^(@) cos^(2)45^(@) cos^(2)60^(@)" cosec"^(2)90^(@)`

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To evaluate the expression \( \sin^2 60^\circ \cdot \cos^2 45^\circ \cdot \cos^2 60^\circ \cdot \csc^2 90^\circ \), we will follow these steps: ### Step 1: Calculate \( \sin 60^\circ \) The value of \( \sin 60^\circ \) is known to be: \[ \sin 60^\circ = \frac{\sqrt{3}}{2} \] ### Step 2: Calculate \( \sin^2 60^\circ \) Now we square the value: \[ \sin^2 60^\circ = \left( \frac{\sqrt{3}}{2} \right)^2 = \frac{3}{4} \] ### Step 3: Calculate \( \cos 45^\circ \) The value of \( \cos 45^\circ \) is: \[ \cos 45^\circ = \frac{\sqrt{2}}{2} \] ### Step 4: Calculate \( \cos^2 45^\circ \) Now we square the value: \[ \cos^2 45^\circ = \left( \frac{\sqrt{2}}{2} \right)^2 = \frac{2}{4} = \frac{1}{2} \] ### Step 5: Calculate \( \cos 60^\circ \) The value of \( \cos 60^\circ \) is: \[ \cos 60^\circ = \frac{1}{2} \] ### Step 6: Calculate \( \cos^2 60^\circ \) Now we square the value: \[ \cos^2 60^\circ = \left( \frac{1}{2} \right)^2 = \frac{1}{4} \] ### Step 7: Calculate \( \csc 90^\circ \) The value of \( \csc 90^\circ \) is: \[ \csc 90^\circ = \frac{1}{\sin 90^\circ} = \frac{1}{1} = 1 \] ### Step 8: Calculate \( \csc^2 90^\circ \) Now we square the value: \[ \csc^2 90^\circ = 1^2 = 1 \] ### Step 9: Combine all the values Now we can substitute all the calculated values back into the original expression: \[ \sin^2 60^\circ \cdot \cos^2 45^\circ \cdot \cos^2 60^\circ \cdot \csc^2 90^\circ = \frac{3}{4} \cdot \frac{1}{2} \cdot \frac{1}{4} \cdot 1 \] ### Step 10: Perform the multiplication Now we multiply these fractions: \[ \frac{3}{4} \cdot \frac{1}{2} = \frac{3}{8} \] \[ \frac{3}{8} \cdot \frac{1}{4} = \frac{3}{32} \] \[ \frac{3}{32} \cdot 1 = \frac{3}{32} \] ### Final Answer Thus, the final answer is: \[ \frac{3}{32} \]
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