# Tagged Questions

31 views

### Making a change of variable to transform an equation

$\displaystyle m\frac {dv} {dt} = mg - kv^2$ $\displaystyle\frac {dV}{dT} = 1 - V^2$ Make a change of variable $v=aV$ and $t=bT$, show that for suitable choices of the parameters $a>0$ and ...
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### Transformation of Cubic Polynomial

I'm stuck on transforming this equation and am not sure where to begin. I know I need to define $x$ as some multiple of $u$ and somehow cancel the coefficient of the $x^2$ term but am not sure how to ...
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### Hodograph transformation and implicit solution of a non-linear PDE

I am trying to understand how can one apply the Hodograph transformation to a non-linear PDE. I read that this transformation implies the representation of the solution in the implicit form . So, if I ...
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### Diff eq. transformation polar coordinates

I have $(x',y')=(x-y-x(x^2+y^2)+\frac{xy}{\sqrt{x^2+y^2}},x+y-y(x^2+y^2)-\frac{x^2}{\sqrt{x^2+y^2}} )$ Now I want to use polar coordinates $(x,y)=(r\cos(t),r\sin(t))$ to get ...
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### Riccati equation transformation

Is possible to transform this Riccati equation into a linear differantial one? Thank you. $$y=y_1+\frac{1}{z}$$
I'm trying to transform an equation of the form $$yw''(y) - [b - ay] w'(y) - [d + ey]w(y) = 0$$ into the form of a Kummer's or confluent hypergeometric differential equation:  y w''(y) + [f - ...
I had a final in differential equations with the first question being: "1. Does the Laplace transform of $\displaystyle \frac{1}{(1+t)}$ exist? Why or why not?" and number 2 was "2. If number one ...