Given a function value of an acute angle, find the other five trigonometric function values.

Question

Sin 0=3/5

Answer 1

This can be done, but it is desirable to know exactly in which quadrant the angle's terminal side is located. Let's assume first quadrant, where ALL trig function values are positive.

 

Using the Pythagorean identity, cos θ = 4/5.  Therefore tangent is 3/4 (ratio of sine to cosine).

 

The other three trig values are reciprocals, so you'll have them in a flash!