Question

How do you find the value of `sin 630`?

Answer 1

`-1`

Explanation:

First, `sin630^@` means that it makes more than one cycle around the axes. That means that we can subtract one cycle, or `360^@`, and the sine of that will still be the same.

So:
`630^@ - 360^@ = 270^@`

At `270^@`, the coordinate is on the negative `y`-axis, or at the coordinate `(0, -1)`.

We know that the cosine of an angle is the `x`-coordinate and the sine of an angle is the `y`-coordinate. That means that `sin270^@ = -1`.

Hope this helps!

Answer 2

`sin630 = -1`

Explanation:

630-360 = 270 degree

the coordinate of 270 degrees (`3pi/2`) in the unit circle is (0,-1)
and sin is the y-value of the coordinate so sin630 is -1