SOLUTION: Use the given information to find each value.
sint=(-12/13) π < t < 3π/2
(a) cos 2t
(b) sin 2t
(c) cos(t/2)
(d) sin(t/2)
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-> SOLUTION: Use the given information to find each value.
sint=(-12/13) π < t < 3π/2
(a) cos 2t
(b) sin 2t
(c) cos(t/2)
(d) sin(t/2)
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Question 499494: Use the given information to find each value.
sint=(-12/13) π < t < 3π/2
(a) cos 2t
(b) sin 2t
(c) cos(t/2)
(d) sin(t/2) Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! Use the given information to find each value.
sint=(-12/13) π < t < 3π/2
(a) cos 2t
(b) sin 2t
(c) cos(t/2)
(d) sin(t/2)
**
sint=(-12/13)
You are working with 5-12-13 right triangle in quadrant III where sin and cos are<0
cost=(-5/13)
..
(a) cos 2t=cos^2t-sin^2t=(-5/13)^2-(-12/13)^2=0.1479-0.8521=-0.7042
(b) sin 2t=2sintcost=2(-12/13)(-5/13)=0.7101
(c) cos(t/2)=±√((1+cost)/2)=-√((1-5/13)/2)=-√0.3077=-0.5547 (choose negative root because t/2 is in quadrant II where cos is <0
(d) sin(t/2)=±√((1-cost)/2)=√((1+5/13)/2)=√0.6923=0.8320 (choose positive root because t/2 is in quadrant II where sin is >0
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