Pre-Cal - Someone please help! (Image Attached)

Mathematics

1 answer:

olasank [31]4 years ago

6 0

Note that $\displaystyle{ \sin30^{\circ}= \frac{1}{2}$ and $\displaystyle{ \cos30^{\circ}= \frac{ \sqrt{3}}{2}$ .

From the unit circle, we can check that $\sin30^{\circ}$ and $\sin(-30)^{\circ}$ have the same value, but opposite signs, that is:

$\sin(-30)^{\circ}=-\sin(30)^{\circ}=-\frac{1}{2}$ .

Thus,
$\displaystyle{ \cos(x-y)= \cos(-30^{\circ}-60^{\circ})=cos(-90^{\circ})$ .

Note that $cos(-90^{\circ})$ is the x-coordinate of the lowest point on the unit circle, that is (0, -1). Thus $cos(-90^{\circ})=0$

Answer: 0

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Can someone help? Show work

Kamila [148]

Given the isosceles right triangle in which each of its legs has a measure of 4:

Let c = hypotenuse
a = one of the legs of the triangle
b = the other leg of the triangle

Use the Pythagorean Theorem to solve for the measure of the hypotenuse:

c^ 2 = a^2 + b^2

c^ 2 = (4)^2 + (4)^2
c^ 2 = 16 + 16
c^2 = 32

Next, take the square root of each side of the equation to solve for c:

√(c^2) = √(32)

c = 4√(2)

Therefore, the correct answer is Option 3) 4√(2).

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3 years ago

Jon is decorating a panner for a parade. Jon uses a piece of red ribbon witch is 3 4ths yard long. Jon also needs blue ribbon th

SVEN [57.7K]

Answer:

John needs $3\frac{3}{4}$ yards of blue ribbon.

Step-by-step explanation:

We have been given that Jon uses a piece of red ribbon witch is 3/4th yard long. Jon also needs blue ribbon that is 5 times as long as the ribbon. We are asked to find the amount of blue ribbon that John needs.

To find the amount of blue ribbon that John needs, we will multiply amount of red ribbon by 5 as shown below:

$\text{Amount of blue ribbon}=5\times \frac{3}{4}$