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doppelgreener
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Why don't Javascript Math.cos doesn't match this vector tutorial?

I'm following this MATHguide lesson on combining vectors and have reached this part:

Next, we need to convert their forces to horizontal and vertical components. Let's use k for Kim's vector and n for Noah's vector.

k = <30, 130°> = <30 cos 130°, 30 sin 130°> = <-19.3, 23.0>. n = <40, 65°> = <40 cos 65°, 40 sin 65°> = <16.9, 36.3>.

To get the X part of Kim's vector, I run 30 * Math.cos(130), I get -11.018739913640896, which is not -19.3. To get the Y part of Kim's vector, I run 30 * Math.sin(130) which is -27.903178505602853, which is not the 23.0 listed by the example.

Where did I go wrong?