Recent content by shemer77

Just curious to find what others think about cheating in school. Whether it is ethical or just totally wrong or somewhere in between? For instance if your struggling to catch up in school and you know you don't have time to finish a homework assignment do you think it would ok to cheat in that...

hmm okay thanks I think I figured it out. All I did was use the equations x = p*cosphi, y=p*sinphi and plugged those into the original equation which was already in cartesian for me.

Hmm ok but why does he have .5 twice as in .5(ap.ax)ax +.5(ap.ax)ay?

Homework Statement Here is the problem and solution but I am confused as to part B http://gyazo.com/e77d05fc67cb6ac266ff021ef88052dc The Attempt at a Solution I understand the first part, but I am totally lost on how they reached their cartesian answer for part B. Firstly why did they...

Hmm ok I think I understand the second one but for the first one what I've been taught is (1-y2)'=1'-y2'=-2y where does that extra y' come from?

Homework Statement http://gyazo.com/d875970963124b7d4a64acc887f168fa The Attempt at a Solution I don't understand the part where they take the derivative of a diff eq to find the higher derivatives can somebody explain it? Mainly the answer where they get y''=(y'')'=(1-y^2)'=-2yy'(this...

Homework Statement http://gyazo.com/6c440aa92106f729639c91f6d59dcd89 The Attempt at a Solution My question is why is yp = At^3+Bt^2 +Ct. The reason I ask that is because is see t^2+2t so why wouldn't it be yp=At^2 +Bt +c?

Homework Statement x*y2(dy/dx)=y3-x3 solve the problem Homework Equations The Attempt at a Solution My answer was (x3/3)+c=y/x there is no answer in the back of the book for this one so i just want to make sure i got it right

thats what i did, and when i reduced it down i got this du/dx+2u/3x=-1/(u^8*x^2) but I've rechecked and rechecked and i can't see if i did something wrong or what I am supposed to do next?

Homework Statement x2*(dy/dx)-2xy=3y4 y(1)=1/2 The Attempt at a Solution the most I have it reduced to du/dx+2u/3x=-1/(u^8*x^2)

still don't really understand part 1, thanks i got part 2, was just a stupid mistake on my part and for part 3 i know how exponents work in the sense that i am taking the nth root of z but how does one convert that to a polar form.

Homework Statement I have some trouble understanding some of my math homework maybe somebody can help me out? 1) find all the values of ln(e) (-1)^i I know that i am going to have to use eulers formula in some way i believe but I am not really sure what the question is asking, what...

wow I am an idiot. so the equation i found was sa=double integral of the sqrt((fx)^2 + (fy)^2 +1) so this was my equation http://gyazo.com/a90a63c1d98779233c0a246864823cd4 with the respective integrals of course. is that right? and If it is, i know i have to convert it to polar, which looks...

well i know that a cylinder makes the dr integral go from 0 to sqrt(8), and I know for dθ it goes all the way around so i know that's from 0 to 2pi, and for my integral i just did (x^2+y^2)/2 and then converted that to polar so it would be r^2/2 and then wrote out the complete equation ie...

woops my limits arent right on that, it should go from 0 to sqrt(8). is that what is wrong?