In math class, we are learning about trigonometry. From yesterday’s lesson, we learned that it is about a relationships involving lengths and angles of triangles.

 

The longest side, AB, is called the hypotenuse (hyp).

The side opposite the angle of A, AC, is called the opposite (opp).

The third side of the triangle, BC, is called the adjacent (adj).

Sin A = opposite / hypotenuse

Cos  A= adjacent / hypotenuse

Tan  A = opposite /  adjacent

 

When using calculators, I could know the ratio by pressing the buttons ‘sin’, ‘cos’, or  ‘tan’ .

To know the angle, I would press the buttons ‘sin-1’, ‘cos-1′, or tan-1’.