SOLUTION: The inequality sin x >(or equal to) cos x is true for all values of x in the interval A. 0 < X < 90 B. 0 < X < 360 C. 45 < X < 225 D. 45 < X < 315

Algebra ->  Trigonometry-basics -> SOLUTION: The inequality sin x >(or equal to) cos x is true for all values of x in the interval A. 0 < X < 90 B. 0 < X < 360 C. 45 < X < 225 D. 45 < X < 315      Log On


   



Question 949537: The inequality sin x >(or equal to) cos x is true for all values of x in the interval
A. 0 < X < 90
B. 0 < X < 360
C. 45 < X < 225
D. 45 < X < 315

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The inequality sin x >(or equal to) cos x is true for all values of x in the interval
Trace the points on the unit circle to determine the solution.
Remember x is the cos ; y is the sin
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A. 0 < X < 90
x goes from 1 to 0
y goes from 0 to 1
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B. 0 < X < 360
x goes from 1 to 0 to -1 to 0 to 1
y goes from 0 to 1 to 0 to -1 to 0
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C. 45 < X < 225
x goes from sqrt(2)/2 to -(sqrt(2)/2)
y goes from sqrt(2)/2 to 1 to sqrt(2/3)
That looks like the answer
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45 < X < 315
x goes from sqrt(2) to 0 to -1 to 0 to sqrt(2)2
y goes from sqrt(2)/2 to 1 to 0 to -1 to to -sqrt(2)/2
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Cheers,
Stan H.
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