Maple Atheist

You have a bracelet on each of your 4 limbs. Each bracelet has its colour randomly (and independently) selected, and can be white, black, or red. How many colour combinations could you be wearing?

Any help is appreciated!

What I'd like to find is an online platform where users can submit and remove their content directly, without having to go through a moderator. I'm aware that this is unlikely to work on a large scale, but I'm not working at a large scale. Does anyone know of a platform that would do this?

I've done questions harder than this with no issues, but I simply can't seem to get this one right. Can anyone lend a hand?

The temperature W is given by:

W = 50+xyz

Find the rate of change of temperature with respect to distance at point P(3,4,1) in the direction v<1,2,2>

This seems like it should be a fairly straightforward question. I take the partial derivatives with respect to xyz to get the vector <4,3,12>. I then get the unit vector of v, which is <1/3, 2/3, 2/3>. I take the length of the dot product of those to get 8.4. But the answer the book gives is 34/3, which I can't figure out. I'd be very grateful if someone could help me out here.

The area of a circle diffuses out a constant rate of 0.0000197 m^2/s. Create a formula to find the instantaneous velocity of the radius. Calculus the instantaneous velocity of the radius at 0 and 1 seconds. The circle begins as a single point.

I haven't been able to find a good answer for this.

Working on statics, I've come to a derivation that I can't solve. I'm fairly sure this is correct:

880sin@ - 400tan@ = 196

Aaaaand now I'm stuck. Can anyone help?

I'm starting a collaborative YouTube channel up, and could use some advice on screen capture software/hardware.

Needs: The largest need will be to record my DAW (Digital Audio Workstation), Reason 7.0. Other uses in the future may include games & applications.

Products I've looked at so far: Camtasia, FRAPS, El Gato capture card.

Can any tech people out there give me some advice here, either with these or a different product? Price is a factor, but I may be willing to spend a bit if the results are outstanding. Thanks.

A particle's position is given by : x(t) = (3t - 2t^2)x + (2 + sin(pi*t))y

Find the angle between the acceleration and position vectors at t = 0.5

First, I calculated the acceleration vector to be:

a(t) = -4x - (pi^2)sin(pi*t)y

With a double derivation, which holds up even under a derivation calculator

Then I plugged t=0.5 into both equations, and got

x(.5) = 1x + 2.03y

a(0.5) = -4x - 0.27y

So my vectors are [1, 2.03] and [-4, -0.27]

I can use either trigonometry or the dot product-length-angle relation, and no matter what, I end up with an angle of 120. This is different than the correct answer of 176 degrees, and I have no idea why. Can anyone help?

A particle's position is given by : x(t) = (3t - 2t^2)x + (2 + sin(pi*t))y

Find the angle between the acceleration and position vectors at t = 0.5

First, I calculated the acceleration vector to be:

a(t) = -4x - (pi^2)sin(pi*t)y

With a double derivation, which holds up even under a derivation calculator

Then I plugged t=0.5 into both equations, and got

x(.5) = 1x + 2.03y

a(0.5) = -4x - 0.27y

So my vectors are [1, 2.03] and [-4, -0.27]

I can use either trigonometry or the dot product-length-angle relation, and no matter what, I end up with an angle of 120. This is different than the correct answer of 176 degrees, and I have no idea why. Can anyone help?

Find the line of intersection of the following planes:

3x +2y +z = -1

2x -y + 4z = 5

To my understanding, in theory this should be a simple augmented matrix that just needs to be row reduced. But no matter how I try to do it, I get the following answer:

x = -9t/7 + 9/7

y = -10t/7 - 17/7

z = t

And the correct answer is supposedly:

x = 9t

y = -10t -1

z = -7t +1

I'm extremely frustrated here, can anyone lend a hand?

Find the line of intersection of the following planes:

3x +2y +z = -1

2x -y + 4z = 5

To my understanding, in theory this should be a simple augmented matrix that just needs to be row reduced. But no matter how I try to do it, I get the following answer:

x = -9t/7 + 9/7

y = -10t/7 - 17/7

z = t

And the correct answer is supposedly:

x = 9t

y = -10t -1

z = -7t +1

I'm extremely frustrated here, can anyone lend a hand?

Find the line of intersection of the following planes:

3x +2y +z = -1

2x -y + 4z = 5

To my understanding, in theory this should be a simple augmented matrix that just needs to be row reduced. But no matter how I try to do it, I get the following answer:

x = -9t/7 + 9/7

y = -10t/7 - 17/7

z = t

And the correct answer is supposedly:

x = 9t

y = -10t -1

z = -7t +1

I'm extremely frustrated here, can anyone lend a hand?

Define a random variable X so that:

E[(X-1)^2]=10

E[(X-2)^2]=6

Find E(X) and the variance of X

Yeah...I've made it through the rest of the chapter no problem but this one is murdering me, anyone know what to do?

First, what happened:

In a dark room, I went to plug my ASUS K55V in for a charge. As you may have guessed, I grabbed the wrong cable. What I ended up plugging in was...(prepare for cringe) the power supply for a Casio synthesizer. The instant it plugged in, the laptop shut down completely.

What happened next:

When I plugged the correct charger in, removed the battery, and placed it back in, the laptop actually started normally, and ran for about 20 minutes. It's worth noting that the battery was quite low before the incident, in fact, it probably had about 20 minutes left. However, after 20 minutes, the thing shut down. I can now start it for a few seconds and it seems like it's going to boot up normally, but it won't last longer than about 30 seconds, and often less than 10. Leaving the charge cable in for longer seems to slightly extend the time it stays on for.

I've heard about the nightmares people have experienced plugging the wrong laptop charger into their computer, and this wasn't even supposed to be a charger at all. On the other hand, the fact that I can start my laptop, and that it ran normally for awhile, makes me think that the battery may just not be holding a charge. What do you think, guys? Have I completely destroyed my laptop, or do I need to go battery shopping tomorrow?

A block of weight w sits on a frictionless inclined plane, which makes an angle θ with respect to the horizontal. A force of magnitude F, applied parallel to the incline, pulls the block up the plane at constant speed.

The block moves a distance L up the incline. The block does not stop after moving this distance but continues to move with constant speed. What is the total work Wtot done on the block by all forces? (Include only the work done after the block has started moving, not the work needed to start the block moving from rest.)

I said that it was the change in potential energy, mgh, which would be mgLsin@. But apparently the correct answer is 0. I can't see how this is the case. They justified it by saying there was no change in kinetic energy, which is true, but there is CLEARLY a change in potential energy. So how can no work have been done?

A small block on a frictionless, horizontal surface has a mass of 2.50×10−2kg . It is attached to a massless cord passing through a hole in the surface (the figure (Figure 1) ). The block is originally revolving at a distance of 0.300 m from the hole with an angular speed of 1.85rad/s . The cord is then pulled from below, shortening the radius of the circle in which the block revolves to 0.150 m. Model the block as a particle.

What is the new angular speed?

Here are my steps (note: W is used for omega).

For the larger radius:

W=v/r

v=Wr

v=(1.85)(0.3)

v=0.555m/s

Now substitute v into the smaller radius:

W=v/r

W=(0.555)/(0.15)

W=3.7rad/second

This is exactly half of the correct answer, which is 7.4rad/sec. I have NO IDEA why this is happening, and I'm getting really frustrated. Any help is appreciated.

A 5.50kg ornament is hanging by a 1.10m wire when it is suddenly hit by a 2.00kg missile traveling horizontally at 14.0m/s . The missile embeds itself in the ornament during the collision.

I have absolutely no clue what to do here, would appreciate at least a step in the right direction.

A certain type of thread has a mean tensile strength of 78.3 kg, with a standard deviation of 5.6 kilograms. How is the variance of the sample mean changed when the sample size is increased from 64 to 196?

Not entirely sure what this question is asking, can anyone help?

I'm given the following density function:

f(x) = (3/2)sqrt(x) ; 0<x<1

0 ; elsewhere

Find F(x)

I did the integration, and what I came up with was

F(x) = 0 ; x #< 0 (please note: I'm using the # to mean "or equal to")

x^(3/2) ; 0<x<1

1 ; x #>1

This is pretty close, however, the correct answer has different # placements:

F(x) = 0 ; x < 0

x^(3/2) ; 0#<x<1

1 ; x #>1

I don't understand what I'm doing wrong. If f(x) is 0 until x goes ABOVE zero, then why does F(x) say x has to be BELOW zero to create F(x)=0, and x^(3/2) starts at zero?

I hope this isn't too confusing, I wasn't entirely sure how else to word it. Any help is greatly appreciated.

I'm trying to plot a unit square in Matlab, ie S=[0 1 1 0 0; 0 0 1 1 0].

It should be fairly straightforward, but the graph is shifted over one unit to the right every time I try and plot it, in other words, the origin is at (1,0). What is happening, and is there any way to fix it? I need to rotate the square with rotation vectors and with this quirk it's impossible, the rotated square ends up distorted.

Any help very much appreciated, thanks.