SOLUTION: what are all solutions to each equation in the interval 0 to 2pi. a. 3cos2t=-2 b.-2cospithetha=0.3

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Question 1113608: what are all solutions to each equation in the interval 0 to 2pi.
a. 3cos2t=-2
b.-2cospithetha=0.3
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
what are all solutions to each equation in the interval 0 to 2pi.
a. 3cos2t=-2
cos(2t) = -2/3
2t = arccos(-2/3) = 2.3 radians or 3.98 radians
t = 2.3/2 = 1.15 radians or 3.98/2 = 1.99 radians
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b.-2cos(pithetha )= 0.3
pi*t = arccos(-0.3/2) = 1.72 radians or 4.86 radians
t = 1.72/pi = 0.547 radians or 4.86/pi = 1.547 radians
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Cheers,
Stan H.
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