Find the Values of Other Five Trigonometric Functions
Question:
Find the values of other five trigonometric functions in the following :
\[ \sin x = \frac{3}{5}, \quad x \text{ lies in Quadrant I} \]
Solution
Given,
\[ \sin x = \frac{3}{5} \]
Since \(x\) lies in Quadrant I, all trigonometric functions are positive.
Using the relation:
\[ \sin x = \frac{\text{Perpendicular}}{\text{Hypotenuse}} \]
Take,
\[ \text{Perpendicular} = 3, \quad \text{Hypotenuse} = 5 \]
Using Pythagoras theorem:
\[ \text{Base} = \sqrt{5^2 – 3^2} \]
\[ = \sqrt{25 – 9} \]
\[ = \sqrt{16} = 4 \]
Now find the remaining trigonometric functions.
\[ \cos x = \frac{\text{Base}}{\text{Hypotenuse}} = \frac{4}{5} \]
\[ \tan x = \frac{\text{Perpendicular}}{\text{Base}} = \frac{3}{4} \]
\[ \csc x = \frac{1}{\sin x} = \frac{5}{3} \]
\[ \sec x = \frac{1}{\cos x} = \frac{5}{4} \]
\[ \cot x = \frac{1}{\tan x} = \frac{4}{3} \]
Final Answer
\[ \cos x = \frac{4}{5} \]
\[ \tan x = \frac{3}{4} \]
\[ \csc x = \frac{5}{3} \]
\[ \sec x = \frac{5}{4} \]
\[ \cot x = \frac{4}{3} \]