SOLUTION: given sin theta =-1/2 and sec theta >0,find the exact value of tan 2theta

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Question 614574: given sin theta =-1/2 and sec theta >0,find the exact value of tan 2theta
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
given sin theta =-1/2 and sec theta >0,find the exact value of tan 2theta
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sinx<0 and secx>0 only in quadrant IV
In quadrant IV:
tanx=-1/√3
Identity:
tan(2x)=(2tanx)/(1-tan^2x)
=(-2/√3)/1-(1/3)
=-2√3/2/3
=-6/2√3
=-√3*6/6
=√3