SOLUTION: Given csc theta = (2 sqr3)/(3) and -270 less than 0 less than 180 determine the exact values of theta my work: (2 sqr3)/3 = 1/sin theta sin theta * (2sqr3)/3 =1 sin theta

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Question 1040321: Given csc theta = (2 sqr3)/(3) and -270 less than 0 less than 180
determine the exact values of theta
my work:
(2 sqr3)/3 = 1/sin theta
sin theta * (2sqr3)/3 =1
sin theta = 1/ (2sqr3/3)
sin theta = 3/ (2sqr3)
when I try to find the inverse of sin theta to find the angle, it gives me an error

Found 2 solutions by Boreal, MathTherapy:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
I would go the other way
csc=2 sqrt(3)/3 is 2/sqrt(3)
Therefore the sin is sqrt (3)/2
That occurs at pi/3 and 2pi/3 on the interval 0 to 2 pi (which covers the above.
With the calculator, try entering 3/(2sqrt(3))
You should get 0.8660.
if you enter 3/2 sqrt(3), the calculator will make that 1.5 *sqrt(3), and you can't take the arc sin of it, because it is greater than 1.

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!
Given csc theta = (2 sqr3)/(3) and -270 less than 0 less than 180
determine the exact values of theta
my work:
(2 sqr3)/3 = 1/sin theta
sin theta * (2sqr3)/3 =1
sin theta = 1/ (2sqr3/3)
sin theta = 3/ (2sqr3)
when I try to find the inverse of sin theta to find the angle, it gives me an error
You're on the right track, but need guidance.
You're correct in that: sin+%28theta%29+=+3%2F%282sqrt%283%29%29. However, you MUST RATIONALIZE the denominator.
We then get: sin+%28theta%29+=+3sqrt%283%29%2F%282sqrt%283%29+%2A+sqrt%283%29%29 =====> sin+%28theta%29+=+3sqrt%283%29%2F%282+%2A+3%29 =====> sin+%28theta%29+=+3sqrt%283%29%2F6 =======> cross%283%29sqrt%283%29%2F2cross%286%29 ======> sin+%28theta%29+=+sqrt%283%29%2F2
Now, this is the answer since the EXACT value is required, and since matrix%281%2C3%2C+-+270+%3C+theta+%3C+180%2C+%22=%22%2C+90%5Eo+%3C+theta+%3C+180%5Eo%29,
then sin+%28theta%29+=+sqrt%283%29%2F2 is in the 2nd quadrant, where sin is positive (> 0)