Trigonometry is that branch of mathematics which deals with the real life problems related to angles. Trigo means three sides, so trigonometry is basically a branch of mathematics which relates to the study of three sided figures i.e. triangles, their sides and the angles between them. In trigonometry we take into consideration a Right Angle triangle with acute angles. These Relations are used to solve real life problems related to inclination at a particular Point. Trigonometry is used to find the angles or the distance between the two points when the angle of inclination is known.
We take into consideration only those Triangles in trigonometry where we have a right angled triangle. The most familiar Functions of trigonometry are sin, cos and tan. The study of trigonometry mainly revolves around these three Functions. The values of sin, cos and tan varies with the change of angles. Example sin (0) = 0, sin ( 30 ) = $\frac{1}{2}$.
Some Basic Formulas used in trigonometry called trigonometric ratios are you must be familiar with all these formulas in order to solve different trigonometric problems. Here, is the list of trigonometric formulas which are commonly used to represent the trigonometric ratios.
Sin Ө = $\frac{perpendicular}{Hypotenuse}$ = $\frac{P}{H}$
Cosine Ө = $\frac{base}{Hypotenuse}$ = $\frac{B}{H}$, written as Cos Ө
Tangent Ө = $\frac{perpendicular}{Base}$ = $\frac{P}{B}$ , written as tan Ө
Cosecant Ө = $\frac{hypotenuse}{perpendicular}$ = $\frac{H}{P}$ , written as cosec Ө
Secant Ө = $\frac{hypotenuse}{base}$ = $\frac{H}{B}$, written as Sec Ө
Cotangent Ө = $\frac{base}{perpendicular}$ = $\frac{B}{P}$, written as cot Ө
Thus we observe that a reciprocal relation exist between the above trigonometric ratios.
Thus, Cosec Ө = ($\frac{1}{Sin Ө}$).
Sec Ө = ($\frac{1}{cos Ө}$).
Cot Ө = ($\frac{1}{tan Ө}$).