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Compute sin 15 ^(@) from the functio...

Compute
`sin 15 ^(@) ` from the functions `60^(@) and 45 ^(@)`

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To compute \( \sin 15^\circ \) using the values of \( \sin 60^\circ \) and \( \sin 45^\circ \), we can use the sine subtraction formula. Here’s how we can do it step by step: ### Step 1: Identify the angles We know that: \[ 15^\circ = 60^\circ - 45^\circ \] ### Step 2: Use the sine subtraction formula The sine subtraction formula states: \[ \sin(a - b) = \sin a \cos b - \cos a \sin b \] In our case, let \( a = 60^\circ \) and \( b = 45^\circ \). Therefore: \[ \sin 15^\circ = \sin(60^\circ - 45^\circ) = \sin 60^\circ \cos 45^\circ - \cos 60^\circ \sin 45^\circ \] ### Step 3: Substitute known values We know the following trigonometric values: - \( \sin 60^\circ = \frac{\sqrt{3}}{2} \) - \( \cos 45^\circ = \frac{1}{\sqrt{2}} \) - \( \cos 60^\circ = \frac{1}{2} \) - \( \sin 45^\circ = \frac{1}{\sqrt{2}} \) Substituting these values into the formula gives: \[ \sin 15^\circ = \left(\frac{\sqrt{3}}{2}\right) \left(\frac{1}{\sqrt{2}}\right) - \left(\frac{1}{2}\right) \left(\frac{1}{\sqrt{2}}\right) \] ### Step 4: Simplify the expression Now, we simplify the expression: \[ \sin 15^\circ = \frac{\sqrt{3}}{2\sqrt{2}} - \frac{1}{2\sqrt{2}} \] To combine these fractions, we need a common denominator: \[ \sin 15^\circ = \frac{\sqrt{3} - 1}{2\sqrt{2}} \] ### Final Result Thus, the value of \( \sin 15^\circ \) is: \[ \sin 15^\circ = \frac{\sqrt{3} - 1}{2\sqrt{2}} \] ---
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Knowledge Check

  • The simplifed from of [{:(4 sin 30 ^(@), 2 cos 60^(@)),(sin 90^(@), 2 cos 0^(@)):}][{:(4,5),(5,4):}] is ........

    A
    `[{:(14, 13),(12,14):}]`
    B
    `[{:(13, 14),(14,13):}]`
    C
    `[{:(14, 14),(13,13):}]`
    D
    `[{:(13, 13),(14,14):}]`
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