Given:
To find:
The exact value of cos 15°.
Solution:
Using half-angle identity:
Using the trigonometric identity:
Let us first solve the fraction in the numerator.
Using fraction rule:
Apply radical rule:
Using :
Answer:
a) 24
b) 10
c) 12/13
d) 5/13
e) 12/5
Step-by-step explanation:
a) We can see that the leg opposite <C is AB, and we are given AB = 24
b) We can see the leg adjacent to <C is AC, and we are given that AC = 10
c) The trig function sine is equal to
The opposite, AB, is 24, and the hypotenuse, BC, is 26. We can plug those numbers in:
d)The trig function cosine is equal to
The adjacent, AC, is 10, and the hypotenuse, BC, is 26. We can plug those numbers in:
d)The trig function tangent is equal to
The opposite, AB, is 24, and the adjacent, AC, is 10. We can plug those numbers in:
