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Evaluate: (sec 75^(@))/(cosec 15^(@))...

Evaluate:
`(sec 75^(@))/(cosec 15^(@))`

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The correct Answer is:
To evaluate the expression \(\frac{\sec 75^\circ}{\csc 15^\circ}\), we can follow these steps: ### Step 1: Rewrite \(\csc 15^\circ\) We know that \(\csc \theta = \frac{1}{\sin \theta}\). Therefore, we can rewrite \(\csc 15^\circ\) as: \[ \csc 15^\circ = \frac{1}{\sin 15^\circ} \] ### Step 2: Substitute into the expression Now, substituting this into our original expression gives us: \[ \frac{\sec 75^\circ}{\csc 15^\circ} = \sec 75^\circ \cdot \sin 15^\circ \] ### Step 3: Rewrite \(\sec 75^\circ\) We know that \(\sec \theta = \frac{1}{\cos \theta}\). Thus, we can rewrite \(\sec 75^\circ\) as: \[ \sec 75^\circ = \frac{1}{\cos 75^\circ} \] ### Step 4: Substitute \(\sec 75^\circ\) into the expression Substituting this into our expression gives us: \[ \frac{1}{\cos 75^\circ} \cdot \sin 15^\circ \] ### Step 5: Use the complementary angle identity We can use the identity \(\cos(90^\circ - \theta) = \sin \theta\). Therefore, we have: \[ \cos 75^\circ = \sin(90^\circ - 75^\circ) = \sin 15^\circ \] ### Step 6: Substitute \(\cos 75^\circ\) Now substituting \(\cos 75^\circ\) back into our expression gives us: \[ \frac{1}{\sin 15^\circ} \cdot \sin 15^\circ \] ### Step 7: Simplify the expression Now we can simplify: \[ \frac{\sin 15^\circ}{\sin 15^\circ} = 1 \] ### Final Answer Thus, the value of \(\frac{\sec 75^\circ}{\csc 15^\circ}\) is: \[ \boxed{1} \]
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