tan A = tan B =We can also figure out the values of the sine, cosine, and tangent of the acute angles
in a couple of special (and common) right triangles: the 30°–60° and the 45°–45°
right triangles:
Triangle Mnemonics
A 30°-60°-90° triangle
has 3 different angles
with sides in proportions
1- -2. A 45°-45°-90°
triangle has 3 distinct
angles with sides in
proportions 1-1-.
The number of distinct
angles is what goes under
the root sign.sin 30° = cos 60° = = 0.50cos 30° = sin 60° = ≈ 0.87tan 30° = ≈ 0.58, tan 60° = ≈ 1.73