How do I find the value of sin 150?

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Nghi N. Share
Sep 16, 2015

Answer:

Find sin 150

Explanation:

You may find sin 150 by 2 ways:

First way. Trig Table gives --> sin 150 deg, or #sin ((5pi)/6)#, = 1/2
Second way: by the trig unit circle.

#sin ((5pi)/6) = sin (pi/6) = 1/2#
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Write your answer here...
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Then teach the underlying concepts
Don't copy without citing sources
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Answer

Write a one sentence answer...

Answer:

Explanation

Explain in detail...

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I want someone to double check my answer

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4
Sep 14, 2015

Answer:

Answer is 1/2: Draw a unit circle / memorize some formulas.

Explanation:

Well, on a unit circle these are the definitions of sine, cosine, and tangent values.

sine: y value
cosine: x value
tangent: y/x value

So if you draw a large arc corresponding to 150 degrees from the x axis, counterclockwise, you end up in the 2nd quadrant. Since 150's supplement is 30s, basic trig tells you that the y value for your point is 1/2...and there you go!

If you think this is inconvenient you can memorize formulas like sinx= sin(2pi-x) but well I don't really prefer it. Especially if you're talking about simple angles less than 180.

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