# Precalculus

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Find the exact value of sin 15°.

I got square root of 2-squaroot of 3/2

is that correct?

• Precalculus -

You'd have to get used to being precise with parentheses if you want to do well in maths.

I got "square root of 2-squaroot of 3/2"
means
√2 - √(3/2),
more or less, which is probably not quite what you mean.

sin(15°)
can be found by the half-angle formula
sin(θ/2)
=sqrt((1-cos(θ))/2)
=sqrt((1-cos(30°))/2)
=sqrt((1-(√3)/2)/2)
=sqrt((2-√3)/4)
=sqrt(2-√3)/2
which is very similar to your answer less the parentheses.

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