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What is the value of sin 15^(@) ?...

What is the value of sin `15^(@)` ?

A

`(sqrt(3)-1)/(2sqrt(2))`

B

`(sqrt(3)+1)/(2sqrt(2))`

C

`(sqrt(3)-1)/(sqrt(3)+1)`

D

`(sqrt(3)+1)/(sqrt(3)-1)`

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The correct Answer is:
To find the value of \( \sin 15^\circ \), we can use the sine subtraction formula. The angle \( 15^\circ \) can be expressed as \( 45^\circ - 30^\circ \). ### Step-by-step Solution: 1. **Identify the Angles**: \[ \sin 15^\circ = \sin(45^\circ - 30^\circ) \] 2. **Apply the Sine Subtraction Formula**: The sine subtraction formula states that: \[ \sin(a - b) = \sin a \cos b - \cos a \sin b \] Here, \( a = 45^\circ \) and \( b = 30^\circ \). 3. **Substitute the Values**: \[ \sin 15^\circ = \sin 45^\circ \cos 30^\circ - \cos 45^\circ \sin 30^\circ \] 4. **Use Known Values**: We know: \[ \sin 45^\circ = \frac{1}{\sqrt{2}}, \quad \cos 30^\circ = \frac{\sqrt{3}}{2}, \quad \cos 45^\circ = \frac{1}{\sqrt{2}}, \quad \sin 30^\circ = \frac{1}{2} \] 5. **Substitute the Known Values**: \[ \sin 15^\circ = \left(\frac{1}{\sqrt{2}} \cdot \frac{\sqrt{3}}{2}\right) - \left(\frac{1}{\sqrt{2}} \cdot \frac{1}{2}\right) \] 6. **Simplify the Expression**: \[ \sin 15^\circ = \frac{\sqrt{3}}{2\sqrt{2}} - \frac{1}{2\sqrt{2}} \] Combine the fractions: \[ \sin 15^\circ = \frac{\sqrt{3} - 1}{2\sqrt{2}} \] ### Final Answer: \[ \sin 15^\circ = \frac{\sqrt{3} - 1}{2\sqrt{2}} \]

To find the value of \( \sin 15^\circ \), we can use the sine subtraction formula. The angle \( 15^\circ \) can be expressed as \( 45^\circ - 30^\circ \). ### Step-by-step Solution: 1. **Identify the Angles**: \[ \sin 15^\circ = \sin(45^\circ - 30^\circ) \] ...
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