SOLUTION: How do you find the trigonometric function value of cosine of theta equals 4/9 and theta is in quadrant IV

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Question 919499: How do you find the trigonometric function value of cosine of theta
equals 4/9 and theta is in quadrant IV

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
cosine (theta) = 4/9
use your calculator to find that arc-cosine(4/9) = 63.61220004 degrees.
that's the angle in the first quadrant.
in the fourth quadrant, theta would be equal to 360 - 63.61220004 degrees which the calculator shows as 296.3878 degrees.
find the cosine of 296.3878 degrees in your calculator and it should tell you that the cosine of 296.3878 degrees is equal to .4444444451.
4/9 is equal to .444444444 so you're pretty close with any difference due to rounding error.