3 years ago

There is a photo attachedi know its not A

Mathematics

1 answer:

Anna71 [15]3 years ago

6 0

cos 2x=2 cos ^2 x-1

cos x=sqrt(1+cos 2 x)/2

x=67.5

cos 67.5=sqrt(1+ cos 135)/2

=sqrt(1-cos45)/2

=sqrt(1-sqrt(2)/2)/2

=sqrt(2-sqrt2)/4

You might be interested in

Put in slope-intercept form, then give slope and y-intercept below<br><br> 2x+3y=-6

KATRIN_1 [288]

Y=-2/3x-2
Slope:-2/3

Slope intercept form is y=mx+b. So you have to isolate the y.

Subtract 2x from both sides

3y=-2x-6

Divide 3 from both sides

y=-2/3x-2

6 0

3 years ago

A circle with radius 3 has a sector with a central angle of 1/9 pi radians

Art [367]

The area of sector is 1.57 m²

<u>Explanation:</u>

Given:

Radius, r = 3 m

Central angle of a sector = 1/9π radians

Area of sector, A = ?

We know:

Area of sector, A = $\frac{1}{2} r^2 \alpha$

where,

α is the central angle in radians

On substituting the value we get:

$A = \frac{1}{2} X(3)^2 X \frac{1}{9}X 3.14\\ \\A = 1.57 m^2$

Therefore, the area of sector is 1.57 m²

5 0

3 years ago

The temperature inside the lab refrigerator is less than 40

Delicious77 [7]

What is the question?

4 0

3 years ago

Write the equation in point-slope form. (4,-2) ; m=1/2

andreev551 [17]

$\text{Given that,}\\\\(x_1,y_1) = (4,-2)~~ \text{and slope,}~ m =\dfrac 12\\\\\text{Point - slope form,}\\\\y-y_1 = m(x-x_1)\\\\\implies y -(-2) = \dfrac 12(x-4)\\\\\implies y+2=\dfrac 12(x-4)$

8 0

3 years ago

Read 2 more answers

When is a rhombus a square?

ozzi

A rhombus is a square when the angles are at 90°.

3 0

3 years ago

Read 2 more answers