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Using the special 30-60-90 triagle and the unit circle the sinx= 1/2 is two options 30 degrees and 300 degrees, however 300 degrees is an obtuse angle, leaving our only possibility 30 degrees the cos of 30 degrees is *I cannot find the square root symbol but* square root of 3/ 2

Use the formula (sin (theta))^2 + (cos (theta))^2 = a million (cos (theta))^2 = a million - (sin (theta))^2 = a million - (a million/2)^2 = a million - a million/4 = 3/4 cos (theta) = sqrt (3/4) = +/- sqrt (3) / 2 yet if you consider that theta is an acute attitude, cos (theta) would be useful. for this reason, cos (theta) = sqrt (3) / 2