All categories

3 years ago

Can someone help me please

Mathematics

1 answer:

White raven [17]3 years ago

4 0

Answer:

Option 1

Step-by-step explanation:

You might be interested in

Use a half-angle identity to find the exact value

Tatiana [17]

Given:

$\cos 15^{\circ}$

To find:

The exact value of cos 15°.

Solution:

$$\cos 15^{\circ}=\cos\frac{ 30^{\circ}}{2}$

Using half-angle identity:

$$\cos \left(\frac{x}{2}\right)=\sqrt{\frac{1+\cos (x)}{2}}$

$$\cos \frac{30^{\circ}}{2}=\sqrt{\frac{1+\cos \left(30^{\circ}\right)}{2}}$

Using the trigonometric identity: $\cos \left(30^{\circ}\right)=\frac{\sqrt{3}}{2}$

$$=\sqrt{\frac{1+\frac{\sqrt{3}}{2}}{2}}$

Let us first solve the fraction in the numerator.

$$=\sqrt{\frac{\frac{2+\sqrt{3}}{2}}{2}}$

Using fraction rule: $\frac{\frac{a}{b} }{c}=\frac{a}{b \cdot c}$

$$=\sqrt{\frac {2+\sqrt{3}}{4}}$

Apply radical rule: $\sqrt[n]{\frac{a}{b}}=\frac{\sqrt[n]{a}}{\sqrt[n]{b}}$

$$=\frac{\sqrt{2+\sqrt{3}}}{\sqrt{4}}$

Using $\sqrt{4} =2$ :

$$=\frac{\sqrt{2+\sqrt{3}}}{2}$

$$\cos 15^\circ=\frac{\sqrt{2+\sqrt{3}}}{2}$

5 0

3 years ago

Find the measure of the missing value in the

kumpel [21]

Answer:

12.6

Step-by-step explanation:

The two left sides have lengths, so this allows you to establish the ratio of the lengths of the sides of the triangles,

left triangle : right triangle

ratio = 25 : 17.5

The bottom sides are also in the same ratio.

ratio = 18 : w

Write a proportion by setting the ratios equal and solve for w.

25/17.5 = 18/w

Cross multiply.

25w = 17.5 * 18

25w = 315

w = 12.6

Answer: 12.6

4 0

2 years ago

Suppose there were m married couples, but that d of these 2m. people have died, Regard the d deaths as striking the 2m people at

iren2701 [21]

The function that represents surviving people are X = 2m - d

Given that there are m married couples and d of the 2m of these couples have died, the total people that remain is expressed as:

Total people remaining = Total married couple - those that died

Total married couple = 2m

Total people that died = d

Taking the difference to get the remaining people;

Total people remaining = 2m - d

Hence the function that represents surviving people are X = 2m - d

Learn more on difference here: brainly.com/question/2605546

6 0

2 years ago

The chart shows Daniela’s run through her race.

Nutka1998 [239]

So it would be c the

8 0

2 years ago

Use graphing to determine the solution to the system of linear equations

saw5 [17]

D) because a straight line has an infinite solution

3 0

2 years ago