This chapter develops work on sines, cosines, and tangents. When you have completed it, you should
1. know the shapes of the graphs of sine, cosines, and tangents for all angles.
2. know, or be able to find exact values of the sines, cosine and tangent of certain special angles.
3. be able to solve simple trigonometric equations.
know and able to use identities involving sine θ, cosine θ and tan θ.
1. Graphs
2. Exact values of some trigonometric functions
There are a few angles which are a whole number of degrees and whose sines, cosines and tangents you can find exactly. The most important of these are 45^o, 60^o and 30^o.
Examples :
You should have memorized this formula : TOA CAH SOH where t=tan ; c=cos ; s=sin ; o=opposite ; a=angle ; h=hypotenuse .
This means that tan θ = O/A ; cos θ = A/H ; sin θ = O/H .
You can press your Casio MS/ES570 calculator to get the exact value too.
FORMULA :
