Recent content by lillybeans

Then suppose for y''-9y'+14y my yp=Ax2e4x Then y'=2Axe4x+4Ax2e4x y''=2Ae4x+8Axe4x+8Axe4x+16Ax2e4x When you plug this all back into the original equation, equate the coefficients to solve for A, it doesn't work. Need more than just one constant.

I don't quite understand why your guess for the particular solution has the form Ax2e4x as opposed to (Ax2+Bx+C)e4x. Shouldn't you use the general form of the second degree polynomial?

Yes, of course, that's why I am asked to find a particular solution. Where did I go wrong? please let me know!

There are two questions that I am trying to solve on web assignment. The goal is to find a general form of a particular solution to each ODE. The question asks me to represent all constants in the solution using "P,Q,R,S,T..etc.", in that order. 1. y'''-9y''+14y'=x2 2. y''-9y'+14y=x2e4x...

Thank you so much! So that's where I went wrong...

When I solve for Isc through a and b using Norton and Thevenin equivalents between c and d I get different results. Why is that? Norton =0.5mA Thevenin =2mA

Thank you for your help! But that would mean my number 2 answer is correct, is it not?

Sorry Sammy, I accidentally read "neither" I thank you both. How about this now?

Hang on. I see that R4 directly connects E and F (due to the short circuit), but how can any current going from E to F passing through R3 NOT also pass through some other resistor?

Because there are nodes in between all resistors, it is almost impossible simplify the circuit using parallel/series connection. Should I redraw the circuit in some way?

One sec.

Homework Statement I got this on a quiz today - Find the equivalent resistance between E and F. Now, the problem with this question is that I get TWO different answers when I trace from: 1. e to f 2. f to e I know one of them is definitely wrong (or maybe both are?), but I don't...

Nevermind I made a mistake, that's why I thought I couldn't turn the last one into an exact one. Thank you once again! :)

[solved]

Sorry, I haven't quite learned that yet. Do you mind elaborating a little? Is that another technique for solving differential equations? Something called substitution, maybe? Thank you