How do I find the value of sin 5pi / 6?

1 Answer
MrsRudolph221 ยท bp
Aug 8, 2015

sin (5pi)/6= 1/2

Explanation:

Sin (5pi)/6= sin (pi- pi/6)= sin pi/6= sin 30 = 1/2

Another way to think about it is to draw the angle in a Unit circle and create the "new" triangle in Quadrant II. teachtogether

Drop a perpendicular to the x-axis and you will have the correct triangle to use.
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(useruploads.socratic.org)

From this triangle, you need the opposite leg length, which is 1/2.
Since the hypotenuse is equal to 1 in the Unit circle, the opposite leg length is the answer for sine. (dividing by 1 is not necessary)

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