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Evaluate (sin35^(@))/(cos55^(@))+(sec20^...

Evaluate `(sin35^(@))/(cos55^(@))+(sec20^(@))/("cosec"70^(@))`.

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To evaluate the expression \((\sin 35^\circ)/(\cos 55^\circ) + (\sec 20^\circ)/(\csc 70^\circ)\), we can follow these steps: ### Step 1: Simplify \(\sin 35^\circ\) and \(\cos 55^\circ\) Using the co-function identity, we know that: \[ \sin(90^\circ - x) = \cos x \] Thus, we can write: \[ \sin 35^\circ = \cos(90^\circ - 35^\circ) = \cos 55^\circ \] So, \(\sin 35^\circ = \cos 55^\circ\). ### Step 2: Substitute into the expression Now, substituting this into our expression gives: \[ \frac{\sin 35^\circ}{\cos 55^\circ} = \frac{\cos 55^\circ}{\cos 55^\circ} = 1 \] ### Step 3: Simplify \(\sec 20^\circ\) and \(\csc 70^\circ\) Next, we simplify \(\sec 20^\circ\) and \(\csc 70^\circ\): \[ \csc 70^\circ = \frac{1}{\sin 70^\circ} \] Using the co-function identity again: \[ \sin 70^\circ = \cos(90^\circ - 70^\circ) = \cos 20^\circ \] Thus, \(\csc 70^\circ = \frac{1}{\cos 20^\circ}\). ### Step 4: Substitute into the expression Now we can rewrite the second part of the expression: \[ \frac{\sec 20^\circ}{\csc 70^\circ} = \frac{\sec 20^\circ}{\frac{1}{\cos 20^\circ}} = \sec 20^\circ \cdot \cos 20^\circ \] Since \(\sec 20^\circ = \frac{1}{\cos 20^\circ}\), we have: \[ \sec 20^\circ \cdot \cos 20^\circ = 1 \] ### Step 5: Combine the results Now we can combine both parts of the expression: \[ 1 + 1 = 2 \] ### Final Answer Thus, the evaluated result is: \[ \boxed{2} \]
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