Cable company marked up monthly cost by 6% .New cost = $63.6
cost before increase = 63.6 × 100/106
= $60
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 
:
Answer:
measure of larger angle = 240 degrees
measure of each of the smaller angles = 120 degrees
Explanation:
In any polygon, the sum of measures of interior angles can be calculated using the following rule:
sum of interior angles = (n-2)*180 where n is the number of sides
Now, for an octagon, n=8, this means that:
sum of measures of interior angles = (8-2)*180 = 1080°
An octagon has 8 interior angles, one of which is twice the measure of the others.
Assume that each of the 7 smaller angles is x degrees and that the larger angle is 2x degrees
Computing their summation, we will find that:
x + x + x + x + x + x + x + 2x = 1080
9x = 1080
x = 120
This means that:
each one of the smaller angles = x = 120 degrees
the larger angle = 2x = 2 * 120 = 240 degrees
Hope this helps :)
