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: ![\sqrt[n]{\frac{a}{b}}=\frac{\sqrt[n]{a}}{\sqrt[n]{b}}](https://tex.z-dn.net/?f=%5Csqrt%5Bn%5D%7B%5Cfrac%7Ba%7D%7Bb%7D%7D%3D%5Cfrac%7B%5Csqrt%5Bn%5D%7Ba%7D%7D%7B%5Csqrt%5Bn%5D%7Bb%7D%7D)

Using
:


45.
12/18 = 8/x <=> 2/3 = 8/x <=> x = (3*8)/2 = 12;
Answer:
15 + .5x = 25
Step-by-step explanation:
.5x = 10
x = 20
Pier pressure lolllllllllllllllllllllllll
Answer: 0.1
Step-by-step explanation: you only need to add zero to the first value,
for example if you have 1/10, you add zero, getting the next equation
10/10 if you add a zero to value you can add a zero to the result getting the following result
10/10=0. in this point both values are divisible
and 10 between 10 is equal to 1
as you finish add zeros you can add a point and after the 1 getting this result
1/10 = 0.1