SOLUTION: give answers in degrees if
sin2 theta+cos theta=0
I am not sure how to start this problem other than sin2 theta would be
(2sin theta cos theta)
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-> SOLUTION: give answers in degrees if
sin2 theta+cos theta=0
I am not sure how to start this problem other than sin2 theta would be
(2sin theta cos theta)
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Question 470370: give answers in degrees if
sin2 theta+cos theta=0
I am not sure how to start this problem other than sin2 theta would be
(2sin theta cos theta) Answer by htmentor(1343) (Show Source):
You can put this solution on YOUR website! give answers in degrees if
sin2 theta+cos theta=0
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You already recognized that you need to use the trig identity sin(2 theta)=2sin(theta)cos(theta)
Substituting that expression gives (and letting theta = x to make it easier to write):
2sin(x)cos(x)+cos(x)=0
cos(x)(2sin(x)+1)=0
This equation is satisfied if either of the two factors are equal to 0.
So we have
cos(x) = 0
2sin(x)+1 = 0
Restricting ourselves to the interval (0,360 deg) the two solutions are
x = 90 deg
sin(x) = -1/2
x = 210 deg