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soldi70 [24.7K]

3 years ago

12

Explain how to find the exact value of cos(75°).

1 answer:

DanielleElmas [232]3 years ago

4 0

Answer:

$\cos(75 \degree) = \cos(45 \degree + 30\degree) \\ \\ = \cos(45\degree) \cos(30\degree) - \sin(45\degree) \sin(30\degree) \\ \\ = ( \frac{1}{ \sqrt{2} } ).( \frac{ \sqrt{3} }{2} ) - ( \frac{1}{ \sqrt{2} } ).( \frac{1}{2} ) \\ \\ = \frac{ \sqrt{3} }{2 \sqrt{2} } - \frac{1}{2 \sqrt{2} } \\ \\ = \frac{ \sqrt{3} - 1}{2 \sqrt{2} } \\ \\ = \frac{0.73205}{2.828427} \\ \\ = 0.2588$

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Look at the picture for the question please show work.

lukranit [14]

$A=\dfrac{1}{2}ah\\
a=25 \text{ mm}\\
h=14 \text{ mm}\\\\
A=\dfrac{1}{2}\cdot25\cdot14\\
A=175 \text{ mm}^2 \Rightarrow C$

6 0

3 years ago

Stacy Smith has a $50,000 loan with a 10% annual interest rate. She paid $250 for a credit report, $300 for attorneys, $250 for

NeTakaya

(250+300+250+5,268)÷50,000
=0.12136*100=12.1%

6 0

3 years ago

Read 2 more answers

Work out the surface area of this cylinder.<br> Radius-7 cm<br> Height-12 cm

RideAnS [48]

Answer:

226pi

Step-by-step explanation:

2 * pi * 7 *(7+12)

4 0

3 years ago

Read 2 more answers

What is the exact distance from (-5,1) to (3,0).

Ilya [14]

Answer:

The distance between the two points is $\sqrt{65} \ \text{units}.$

Step-by-step explanation:

In order to find the distance between two coordinate pairs, we can use the distance formula:

$\displaystyle \bullet \ \ \ d = \sqrt{(x_2-x_1)^2+(y_2-y_1)^2}$

Our coordinate pairs need to be labeled accordingly, so we can use this naming system:

$\bullet \ \ \ (x_1, y_1), (x_2, y_2)$

This assigns a name to our points:

$x_1 = -5$
$y_1 = 1$
$x_2 = 3$
$y_2 = 0$

Therefore, we can plug these into the formula and solve:

$d=\sqrt{(3-(-5))^2+(0-1)^2}\\\\d=\sqrt{(8)^2+(-1)^2}\\\\d=\sqrt{8^2+1^2}\\\\d=\sqrt{64+1}\\\\d=\sqrt{65}$

Therefore, the distance between the two points is $\sqrt{65} \ \text{units}$ .

5 0

2 years ago

pychu [463]

Answer:

<h2> y = x² - 1</h2>

Step-by-step explanation:

y = -1 for x = 0 {point(0, -1)} means -1 at the end of formula

If we add 1 to y-coordinate of every given point we get the squares of x-coordinate:

(1, 0): 1² - 1 = 0

(2, 3): 2² - 1 = 4 - 1 = 3

(3, 8): 3² - 1 = 9 - 1 = 8

(4, 15): 4² - 1 = 16 - 1 = 15

So for any x:

(x, y) y = x² - 1

6 0

3 years ago