1. A

    First Order Non Linear -getting started

    It's been awhile since I've solved a differential equation. The L,D,R,T,M, Re are constants. p(L,t)=(14.7+95t) trying to get a result that shows mass m with respect to time t. m(t)=.....
  2. C

    Second Order Differential Equation

    Y'' + Y = SinX I'm not sure as to what to use as my particular integral, I've tried λsinx and λxsinx which didn't seem to work, I also tried μcosx + βsinx which didn't work either? Could anyone help with which PI to use? Thanks
  3. C

    Need guidance with deriving expression for differential Maxwell Model

    Hi, I require some guidance with this problem below. I'm not sure I understand what to do or what it's asking in the question, where it states "Derive the expression for the differential version" I have attached a PDF document with the Maxwell Model equation, in addition I need to show it by...
  4. E

    Finding the derivative

    Hello. We have an assignment where we have to determine the derivative with respect to x. The problem is f(x)=(sqrt(x+5))/x^2 The answer is We don't know how to get to this answer, if anyone could help out, it would be much appreciated (Happy)
  5. Y

    chemical reaction rate differential equation.

    Hi guys, Need some help with this separable differential equation. I understand that I have to use separation of variables and integration by partial fractions (it is a second order reaction rate equation where K is the reaction rate constant). I can get it to this form...
  6. brandnew

    differential equations and numerical methods questions ??

    i have been trying to follow computer oriented numerical methods in c language for some time now ... these were the things i was supposed to do with a programming language like c ... i have managed it this far ... there were at least 5 books i had to follow ..to understand this...
  7. brandnew

    few more doubts about differential equations ... ?

    i have been self learning maths for some time now ... i am out of college ... and this is what i have been doing with my free time ... its sort of sad , that most forums wont allow me to post pictures of maths related stuff ... and deletes it saying its unrelated and spam ... but i have been...
  8. S

    solve the 1st order unforced differential equation

    solve the 1st order homogeneous differential equation $2t{w}'-3w=0$ WORKED ANSWER For a 1st order homogeneous ODE, have solution formula: $A\cdot e^{-\int p}$ So we are doing the following integration $e^{-\int \frac{3}{2t}}\cdot A$ $\Rightarrow \int 3\cdot \frac{1}{t}\cdot...
  9. brandnew

    few more basic differential equation questions ??

    i was trying to learn differential equations ... i was lucky enough to find some good explanations for calculus and differential equations ... in this equation which is the dependent variables and which one is the independent variables ?? and how do i solve this differential equation...
  10. S

    Solve the differential equation by integration

    having some difficulty with this question help me please guys Solve the differential equation by integration: y' = y Solution is y = c ex but I dont understand it?
  11. M

    first order differential equation help..

    having problems with solving these differential equations... will be very thankful anybody can solve these or give an idea to solve y' =tan (x+y) -1 (x^4 -2xy^2 +y^4 )dx - (2x^2 y -4xy^3 )dy = 0 (y sec^2 x +secx tanx ) dx +(tanx +2y )dy =0
  12. brandnew

    few beginner differential equation questions ...

    i am starting to learn differential equation ... for computer science and programming ... but before that i have few basic questions about some maths terminologies ... what is the difference between an equation and a function ?? how does a simple differential equation looks like ...
  13. U

    Differential Equations...Calculus 2

    We started learning basic ideas in terms of differential equations in Calculus 2. I know how to find the general and particular solutions of basic differential equations. However, I am not clear about the difference between the two ideas. What is a general solution to a differential equation...
  14. M

    Particular Solution of the differential equation

    Determine :- Particular Solution of the differential equation: (12)d^2y/dt2 - 3y = 0 Boundaries t=0, y=3, dy/dt=0.5 Thanks
  15. M

    Second Order Differential

    In a galvanometer the deflection θ satisfies the following differential equation:- (d2θ/dt2) + 2(dθ/dt) + θ = 4 Solve the equation for θ given that when t=0, θ=0 and dθ/dt=0 Thanks in advance!
  16. M

    Find the boundary condition of the nonlinear partial differential equations

    I have first-order nonlinear partial differential equations \frac{du}{dt}+u\frac{du}{dx} =-u^3, u\Bigr|_{t=0}=f(x) solution dt=\frac{dx}{u}=-\frac{du}{u^3} F(x-\frac{1}{u},t-\frac{1}{2u^2}) Need find boundary conditions f(x) (for example u(t=0,x)=x and find $u$) But my simple function have a...
  17. I

    Writing differential equations

    A person receives a drug intravenously at a rate of 3 mg/hr. The drug is eliminated from the body at a rate proportional to the amount present with a constant of proportionality k = -0.4 a) Differential equation for quantity Q of the drug present in the body after t hours This would be dQ/dt =...
  18. P

    Differential of Laplace transform

    I'm taking the Laplace transform of t(y'). The table of transforms says the transform of t^nf(t) is (-1)^nF^n(s). So the transform I want is -d/ds[sY(s)-y(0). I would have thought that derivative would be -Y(s)-o. The class notes say it's -sY'(s)-Y(s). I have no idea why. I don't know if...
  19. B

    Ordinary differential equations - can't follow integration step

    Hi, In my lecture notes is a problem that reads: A radioactive substance decays at a rate proportional to the amount present. If we start with 10gm, how long until only 0.1g remains if the constant of propotionality is k=-1.4^10^-11 sec^-1. The solution says the solution to the ODE dR/dt=kR and...
  20. ishandixit

    Differential Calculus

    I wanted to know what is the derivative of signum function And please help to calculate derivative of signum(x^3)