Find all solutions of the equation in the interval [0, 2pi). (sqrt3)csctheta+2 = 0. Write your answer in radians in terms of pi
\[\sqrt{3}\csc \theta+2=0\]
I rarely use csc or sec, and so would first translate to 1/sin
Okay so \[\sqrt{3}(1/\sin \theta) + 2 = 0\]
now add -2 to both sides, then divide both sides by sqr(3)
you should get \[ \frac{1}{\sin \theta}= - \frac{2}{\sqrt{3}} \]
now invert (i.e. "flip" ) both sides
Okay, got it! Sorry, was following along with you while writing it down on paper
Flip as in, turn upside down?
yes, as in making the left side sin theta instead of 1/sin theta ditto for the right side.
\[\frac{ \sin \theta }{ 1 } = \frac{ -2 }{ \sqrt{3} }\]
yes, but most people would just write sin theta on the left side
oh, you have to flip the right side also
Oh, I forgot to flip the other side, sorry!
\[\sin \theta = -\frac{ \sqrt{3} }{ 2 }\]
usually, people memorize sin of certain angles: 0, 30, 45, 60 and 90 degrees this is one of those angles.
*ignoring the sign, for the time being *
Is it 60? (ignoring the sign)
yes. now we need to find the actual angle to get a general idea, we (maybe?) know that -sqr(3)/2 is about -.8 (roughly) if we plot a sin curve |dw:1469993276069:dw|
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