SOLUTION: Find the exact value of the trigonometric function. sin(3pi/2)

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Question 1203403: Find the exact value of the trigonometric function.
sin(3pi/2)
Found 2 solutions by ikleyn, math_tutor2020:
Answer by ikleyn(52781) About Me  (Show Source):
You can put this solution on YOUR website!
.

-1.

It is what a student studying trigonometry should know as the multiplication table.



Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

Here's a diagram of the unit circle

Image Source:
https://etc.usf.edu/clipart/43200/43216/unit-circle8_43216.htm
This diagram is used a lot in trigonometry. So be sure to have a copy somewhere in your notes.

The angle 3pi/2 is pointing directly south toward 270 degrees.
The associated point on the unit circle is (0,-1)
x = 0
y = -1
The y value is result of sin(3pi/2) because
x = cos(theta)
y = sin(theta)

Therefore, sin(3pi/2) = -1

A calculator can be used to compute this. Make sure the calculator is in radian mode.