if 0*

Question

if 0*<x<360*, solve the equation sin x = -sqrt(3)/2

anonymous · Answer

It is supposed to be 0 degrees < or equal too x < or equal too 360 degrees.

phi · Answer

use <=  or >= if you can't find ≤  (option < on my keyboard... try using various control keys, maybe you will find it..)

anonymous · Answer

haha! ok. so it is supposed to be 0*<= x <= 360*, solve the equation for sin x =-sqrt(3)/2

phi · Answer

the first step is figure out which quadrants  x will be in
you could memorize that sin is neg in the III and IV quadrants
or you could sketch a triangle in each quadrant and see which give you a negative sin

next,  find inverse sin (sqrt(3)/2)   (this is one you should memorize)  or use a calculator if allowed.  this is the angle in the 1st quadrant

finally,  "adjust" the angle to be in quadrant III and quadrant IV  (we get 2 answers)

phi · Answer

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