Solve
\[\cot \theta \cos^2 \theta - 2 \cot \theta = 0\] \[\cot \theta \cos^2 \theta - 2 \cot \theta = 0\] \[\cot \theta (\cos^2 \theta -2) = 0\]
\[0 \le \theta \le 2 \pi\] Angle values are just within the unit circle. No negatives
We still doing these?
I figured you'd have these mastered by now
\[\theta = \frac{ \pi }{ 2 }\] is that the only angle
IDK, what work did you do to get that as the only answer?
\[\cot \theta = 0\] There is \[\cos^2 \theta = 2\] But that can't work
\(\cos \theta = \sqrt{2}\) Basically find the angle
You always reduce down to either \(\sin\theta\) or \(\cos\theta\) with these kinds of problems then find the angle
Doesn't that not fall within the unit circle tho
Okay, then I guess you have your answer then.
But however, you should make sure that there is no other value besides the one you found for the other angle between 0 and 2pi
Yeah that would just be 3pi/2
Correct
Of course, when in doubt, you can just graph it: https://www.desmos.com/calculator/ziffjnwfkh
Also, next time you see \(\cos\theta = \sqrt{2}\) it would make sense that there is no solution for this since the range of cosine theta will always be -1< y < 1. And of course the square root of 2 is greater than one.
mhm. going to get some sleep.
its late for me and probably is for you too
No such thing as too late when you're a mil vet.
sleep is good though so be sure to get some. goodnight
Of course. I always enjoy a good sleep.
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