Answer:
A and D is correct .
Step-by-step explanation:
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:
b = square root of 44 or approx. 6.6
Step-by-step explanation:
I assume the heights are 160 ft and 1480 ft.
The two heights are unknown, so we will use variable h to help solve the problem.
The shorter building, building A, has height h.
Since building A is shorter by 160 ft, then building B is taller by 160 ft, so the height of building B is h + 160.
Now we add our two heights to find the total height.
h + h + 160 is the total height.
We can write it as 2h + 160
We are told the total height is 1480 ft, so we let 2h + 160 equal 1480, and we have an equation.
2h + 160 = 1480
Subtract 160 from both sides
2h = 1320
Divide both sides by 2
h = 660
h + 160 = 820
Building A measures 660 ft.
building B measures 820 ft.
Answer:
<h2><u><em>
2/7</em></u></h2>
Step-by-step explanation:
I answer for what I understand, the question is not clear.
2 divided by what times what equals 7
2 : x = 7
x = -2/-7
x = 2/7
-------------
check
2 : 2/7 = 7
2 * 7/2 = 7
7 = 7
the answer is good
