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3 years ago

What is the exact value of cos 3pi/4

Mathematics

1 answer:

NikAS [45]3 years ago

8 0

Answer:

cos(3π/4) = -√2/2

Step-by-step explanation:

According to the unit circle, the exact value of cos(3π/4) is -√2/2.

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How do I figure out what 1/10 of 6000 is?

alisha [4.7K]

The way I like to figure out problems like this is to write it out like,

1/10 = x/6000
(One over ten equals x over 6000)

Then you find out how much you multiplied 10 by to get 6000. To do this you can divide 6000 by 10 getting 600. The rule "what you do to the bottom you have to do to top" in this equation. So since you multiplied the bottom by 600 you have to multiply the top by 600 as well. 600 times 1 is just 600.

So your answer is, 600 is 1/10 of 6000.

Hope this helps and isn't too confusing.

5 0

3 years ago

d) Jerry, Barry, and Harry went fishing and they each caught a giant fish! Jerry's fish is 62 inches long. Barry's fish is 7 fee

Sauron [17]

No it’s berry 2yards=6feet so they are all smaller than berrys 7foot fish

7 0

3 years ago

Gina is cutting construction paper into rectangles for a project. She needs to cut one rectangle that is 12 inches by 14 1/4 inc

Fittoniya [83]

Answer:

278.63 square inches

Step-by-step explanation:

Gina needs to cut two types of rectangles.

Dimensions of one rectangle is given as,

Width = 12 inches

Length = $14\frac{1}{4}$ = $\frac{57}{4}$ inches

So, the area of this rectangular paper will be

Area = width × length = $12\times \frac{57}{4}$ = 171 inches²

Dimensions of the other rectangular paper has been given as

Width = $10\frac{1}{4}$ = $\frac{41}{4}$ inches

Length = $10\frac{1}{2}$ = $\frac{21}{2}$ inches

So, the area of this rectangle will be

Area = width × length = $\frac{41}{4} \times \frac{21}{2}$ = 107.63 inches²

Thus the total area she need to cut = 171 + 107.63 = 278.63 square inches.

6 0

3 years ago

Read 2 more answers

PLEASE PLEASE PLEASE I BEG YOUWhich graph is a function of x? On a coordinate plane, a vertical line is at x = negative 3. On a

ki77a [65]

Answer:

On a coordinate plane, a v-shaped graph opens up.

Step-by-step explanation:

If you can draw a vertical line that intersects the graph in more than one place, the graph is NOT a function.

It appears your only function is ...

On a coordinate plane, a v-shaped graph opens up.

4 0

3 years ago

Read 2 more answers

A ball is projected in to the air. Its height at time t is given by the equation

Ksju [112]

The equation gives the height of the ball. That is, h is the height of the ball. t is the time. Since we are looking for the time at which the height is 8 (h=8), we need to set the equation equal to 8 and solve for t. We do this as follows:

$h=-16 t^{2} +60t+1$
$8=-16 t^{2} +60t+1$
$16 t^{2} -60t-1+8=0$
$16 t^{2} -60t+7=0$

This is a quadratic equation and as it is set equal to 0 we can solve it using the quadratic formula. That formula is:
$t= \frac{-bplus minus \sqrt{ b^{2}-4ac } }{2a}$
You might recall seeing this as "x=..." but since our equation is in terms of t we use "t-=..."

In order to use the formula we need to identify a, b and c.
a = the coefficient (number in front of) $t^{2}$ = 16.
b = the coefficient of t = -60
c = the constant (the number that is by itself) = 7

Substituting these into the quadratic formula gives us:
$t= \frac{-(-60)plus minus \sqrt{ (-60)^{2}-4(16)(7) } }{2(16)}$
$t= \frac{60plus minus \sqrt{3600-448 } }{32}$
$t= \frac{60plus minus \sqrt{3152 } }{32}$

As we have "plus minus" (this is usually written in symbols with a plus sign over a minus sign) we split the equation in two and obtain:
$t= \frac{60+56.1426}{32} =3.63$
and
$t= \frac{60-56.1426}{32} =.12$

So the height is 8 feet at t = 3.63 and t=.12

It should make sense that there are two times. The ball goes up, reaches it's highest height and then comes back down. As such the height will be 8 at some point on the way up and also at some point on the way down.

3 0

4 years ago