Find the equivalent expression.

a pipe made of metal 1 cm thick hasan external radiusof 6 cm. Find the volume of metal used in making 4m height of pipe

Dmitrij [34]

To get the answer you will need to do pi times r squared times height which is 36pi in other words 113.097

3 0

3 years ago

HELP HELP ASAP!!!!!!!!!!!!!!!!!!!!

Keith_Richards [23]

Answer:

You don't need help you got this

Step-by-step explanation:

no you don't got this now do your work and stop reading this bye :)

5 0

3 years ago

What is the value of x?<br> (2x + 2)<br> (3x - 527<br> Enter your answer in the box.<br> Next

telo118 [61]

Answer:

The roots (zeroes) are -1 and 527 over 3.

Step-by-step explanation:

First, you gotta do the FOIL method and multiply the values which gives u 6x^(2) -1048x - 1054. Then you find the zeroes ( the points in which the the graph intersects with the x-axis). Finally, you set y equal to zero and find the x.

4 0

3 years ago

Read 2 more answers

If a projectile is fired with an initial speed of vo ft/s at an angle α above the horizontal, then its position after t seconds

Elena L [17]

Answer:

a) The bullet hits the ground after 64 seconds.

b) The bullet hits the ground 113,511.7 feet away.

c) The maximum height attained by the bullet is of 16,384 feet.

Step-by-step explanation:

Equations of motion:

The equations of motion for the bullet are:

$x(t) = (v_0\cos{\alpha})t$

$y(t) = (v_0\sin{\alpha})t - 16t^2$

In which $v_0$ is the initial speed and $\alpha$ is the angle.

Initial speed of 2048 ft/s at an angle of 30o to the horizontal.

This means that $v_0 = 2048, \alpha = 30$ .

So

$x(t) = (v_0\cos{\alpha})t = (2048\cos{30})t = 1773.62t$

$y(t) = (v_0\sin{\alpha})t - 16t^2 = (2048\sin{30})t - 16t^2 = 1024t - 16t^2$

(a) After how many seconds will the bullet hit the ground?

It hits the ground when $y(t) = 0$ . So

$1024t - 16t^2 = 0$

$16t^2 - 1024t = 0$

$16t(t - 64) = 0$

16t = 0 -> t = 0 or t - 64 = 0 -> t = 64

The bullet hits the ground after 64 seconds.

(b) How far from the gun will the bullet hit the ground?

This is the horizontal distance, that is, the x value, x(64).

$x(64) = 1773.62(64) = 113511.7$

The bullet hits the ground 113,511.7 feet away.

(c) What is the maximum height attained by the bullet?

This is the value of y when it's derivative is 0.

We have that:

$y^{\prime}(t) = 1024 - 32t$

$1024 - 32t = 0$

$32t = 1024$

$t = \frac{1024}{32} = 32$

At this instant, the height is:

$y(32) = 1024(32) - 16(32)^2 = 16384$

The maximum height attained by the bullet is of 16,384 feet.

7 0

3 years ago

Eloise started to solve a radical equation in this way: square root of negative 2x plus 1 − 3 = x square root of negative 2x plu

Rasek [7]

Answer:

Both solutions cannot satisfy the original equation as Eloise makes mathematical error in solving for those solutions. Check Explanation for the breakdown of her steps and the right way to go about solving this.

Step-by-step explanation:

Radical equation is square root of negative 2x plus 1 − 3 = x

In mathematical terms,

√(-2x + 1) - 3 = x

Them her steps,

She adds 3 to both sides,

square root of negative 2x plus 1 − 3 + 3 = x + 3

In mathematical terms,

√(-2x + 1) - 3 + 3 = x + 3

On simplification, she obtains,

square root of negative 2x plus 1 = x + 3

√(-2x + 1) = x + 3

Then, she goes ahead to subtract 1 from both sides,

square root of negative 2x plus 1 − 1 = x + 3 − 1

√(-2x + 1) - 1 = x + 3 - 1

It was at this point that she makes the mistake that scatters everything; she removed the 1 from under square root to take the (- 1) she introduced (without much thoughts). She then obtains

square root of negative 2 x = x + 2

√(-2x) = x + 2 (wrong step, that scatters the process)

She then squares both sides

(square root of negative 2x)² = (x − 4)²

-2x = (x - 4)²

Here, Eloise makes another error, albeit, this is a typographical error. She wrote (x - 4) instead of (x + 2)

From then on, anything she does, whether wrong or right, it will not give the right answer.

−2x = x² − 8x + 16

Then she makes more errors, (-8x) changes to 8x with the introduced 2x on the left hand side doesn't account for this change.

−2x + 2x = x² + 8x + 16 + 2x

0 = x² + 10x + 16

0 = (x + 2)(x + 8)

x+2 = 0 or x+8 = 0

x = -2 or x = -8

Which is evidently wrong.

The correct solving method should have been from the point

√(-2x + 1) = x + 3

Square both sides

-2x + 1 = (x + 3)²

x² + 6x + 9 = - 2x + 1

x² + 8x + 8 = 0

Solving the equation quadratically.

x = - 1.17 or - 6.83

The true value of x that satisfies the given equation that Eloise attempted to solve are -1.17 and -6.83.

Hope this Helps!!!

8 0

3 years ago