Example;

In angle XYZ, angle Y = 90^o, XY = 57cm and YZ = 38cm. Find XZ, angle X and angle Z, giving answer correct to one decimal place (1d.p).

Solution;

Trigonometric ratios

•   The certain ratios involving the sides of a right angled triangle are called Trigonometric ratios.

       Suppose: b is the base

       h is the hypotenuse

       p is perpendicular

       then,

       Reciprocals of the ratios are:

       Cosec A= 1/sin A= h/p

       Sec A= 1/cos A= h/b

       Cot A= 1/tan A= b/p

•   Sin θ is a single symbol and sin cannot be detached from ‘θ. And sin θ ≠ sin X θ.

       This remark is true for other ratios as well

       Trigonometric /Ratios of some specific angles

       The specific angles are 0°, 30°,45°, 60°, 90°. These are given in the following table