Before defining the TRIGONOMETRIC FUNCTIONS, we must see how to relate the angles and sides of a right triangle.
A right triangle is composed of a right angle, the angle at C (90 degree, the symbol is small square), and two acute
angles, which are angles less than a right angle. It is conventional
to label the acute angles with Greek letters but for simplicity I will just use English alphabet. For the given figure above the said acute...
