and hypotenuse c>0 as in Figure 1 below:  |
| Figure 1 |
pictured in the figure, we see that  |  |
 |  |
 |  |
Trigonometric functions
Consider the triangle with sides of length and hypotenuse c>0 as in Figure 1 below:
For the angle pictured in the figure, we see that
and hypotenuse c>0 as in Figure 1 below: pictured in the figure, we see that 
