SOLUTION: If cos(a) = sin(52°), what is the value of a? A.28 ° B.38° C.52° D.128 °

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Question 1141319: If cos(a) = sin(52°), what is the value of a?
A.28 °
B.38°
C.52°
D.128 °
Answer by greenestamps(13209) About Me  (Show Source):
You can put this solution on YOUR website!


Picture a right angled triangle. The other two angles are complementary (sum to 90 degrees).

By the basic definition of sine and cosine in terms of adjacent, opposite, and hypotenuse, the sine of one angle is the cosine of the other, and vice versa.

So the sine of an acute angle is the cosine of the complement of the angle; and the cosine of an acute angle is the sine of the complement of the angle.

So sin(52) is equal to cos(90-52) = cos(38).