Answer:
The answer to your question is the letter C.
Step-by-step explanation:
Data
sin Ф = 1/5
cos Ф = ?
To solve this problem use trigonometric functions.
1.- The first condition is that the angle must be in the first quadrangle
(0° < Ф < 90°).
2.- Write the trigonometric function sine.
sin Ф = Opposite side / hypotenuse and sin Ф = 1/5
then, Opposite side = 1 hypotenuse = 5
3.- Use the Pythagorean theorem to find the adjacent side.
Hypotenuse² = Opposite side² + Adjacent side²
-Solve for Adjacent side
Adjacent side² = Hypotenuse² - Opposite sie²
-Substitution
Adjacent side² = 5² - 1²
-Simplification
Adjacent side² = 25 - 1
Adjacent side ² = 24
Adjacent side = √24
4.- Find the cosФ
cos Ф = Adjacent side/hypotenuse
-Substitution
cosФ = √24 / 5
