Recent content by korican04

First when doing these problems put all the xs and ys on one side of the equations. So first you'll have x'-4x - y = 2t 2x + y' - y = 0 Now factor the differential operator "D" from the differentials. (I'm assuming x and y are functions of t) (D-4)x + 3y = 2t 2x + (D-1)y = 0 This gives you...

I obtained the same v as you, but what did you use for the force? I used F=q(vxB), in this case v cross B is vB because they are perpendicular. F= qvB = mv^2/r r=mv/qB

Sorry but isn't I= pave/(4*pi*r^2) ?

I believe that this is correct. If X Y and Z are independent then a random variable say A=X+Y+Z would have a poisson distribution with rate of \lambda_X +\lambda_Y+\lambda_Z Although you initially wrote \lambda_Z =3 ,but put down 4.

You need to evaluate each laplace transform now. For example the Laplace transform of sin(t) L[sin(omega*t)] = omega / ( s^2 + omega^2) You also have to use the properties of laplace transforms especially the time shift property. Or you can just do the integrals for each, you get the same...

For normal distributions you can use the properties if X1 and X2 are two independent random variables then Y=aX1+bX2 is a random variable with normal distribution and mean a*u1+b*u2 and variance a^2*sigma1^2+b^2*sigma2^2 So in our case Y=X1-X2, mean = 1*63+-1*63=0 variance =...

Do you know how to take a derivative? dx/dt = 2t m/s dy/dt= 6-3t m/s At t=2 dx/dt=4 m/s dy/dt=0 m/s v= 4 m/s in the x direction.

When you add complex numbers it is the same as adding 2d vectors. so your radius = sqrt[ (x1+x2)^2 + (y1+y2)^2] angle = tan-1 [(y1+y2)/(x1+x2)] x=radius*cos (angle) y=radius*sin(angle) After some expansion and trig formulas r= sqrt[r^2 + R^2 + 2rRcos(theta-phi)] angle=tan-1[...

Try using Y=X1-X2 as a new random variable with mean 0 and standard deviation of sqrt(2)*21 P(Y>5) Z=(Y-mean)/std P(Z>.052) = 1-P(Z<.052) so now you can find the values in a z-table. I haven't thought of the other case in which X2>X1, but this is at least how you should think about the...

The prob that First person on standby would get on: P(Y=<49) you would need one person or more to not show up. The third would be P(Y=<47)

Msubx(t) = e^(3t+8t^2) is the moment generation function for a normal distribution. The moment-generating function of N(mean,sigma_squared) is Msubx(t)= e^(mean*t+.5*sigma_squared*t^2), so in this case the mean is 3 and sigma_squared = 16, Now try finding the mu and sigma for Z based on the...

Oh I see what you are confused about. The table of values represent the probability of how many people actually show up. So if only 49 people out of the 55 tickets sold show up everyone will be accommodated. If 51 people show up, then not everyone will be accommodated. Just because 55 people...

My bad i didn't add them correctly. Right, so you can add the probabilities up to 50. You still get the same answer.

It asks what's the probability that all ticketed passengers who show up will get a seat. So if 51,52, 53,54 or 55 passengers show up then there are some who don't get seats. So you have to compute what's the probability that 50 or less passengers show up. If you add up the probabilities on...

Isn't it just the P(Y=<50)