Question
Download Solution PDFComprehension
What is equal to?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFCalculation:
Given,
Let\(p = \sin 35^\circ \),\(q = \sin 25^\circ \) and \(r = \sin(-95^\circ) \)
We need to find the value of p + q + r .
First, we know that:
\( \sin(-95^\circ) = -\sin(95^\circ) \).
Thus, the expression p + q + r becomes:
\( p + q + r = \sin 35^\circ + \sin 25^\circ - \sin 95^\circ \).
Using the identity for the sum of two sine functions:
\( \sin A + \sin B = 2 \sin \left( \frac{A + B}{2} \right) \cos \left( \frac{A - B}{2} \right) \).
Substitute \(A = 35^\circ \) and \(B = 25^\circ \)
\( \sin 35^\circ + \sin 25^\circ = 2 \sin 30^\circ \cos 5^\circ \).
Since \(\sin 30^\circ = \frac{1}{2} \), we get:
\( \sin 35^\circ + \sin 25^\circ = \cos 5^\circ \).
Now, we know that:
\( \sin 95^\circ = \cos 5^\circ \).
Therefore:
\( p + q + r = \cos 5^\circ - \cos 5^\circ = 0 \).
∴ The value of p + q + r is 0.
Hence, the correct answer is Option 0.
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