Consider the differential equation dy/dx = (y-1)^2 cos(Πx)

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HW help!

Homework Statement



consider the differential equation dy/dx = (y-1)^2 cos(Πx)

a.There is a horizontal line with y =c that satisfies this equation. Find the value of c
b. Find the particular solution y =f(x) tot the differential equation with the initial condition f(1) = 0

Homework Equations



n/a

The Attempt at a Solution



I tried to do the problem, but I can't separate the y variables from the x, help!
 
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(a) What happens when you plug y=c to the differential equation? You should get just an equation depending on c (and x, but if you restrict x, you can divide it out).
(b) Try multiplying each side by dx/(y-1)^2 and integrating directly. Then, you can either use your initial conditions as your integration limits or plug them into find your integration constant.
 
I got it, I got c=1 thanks
 
While it is, in fact, almost trivial to separate x and y ((y-1)2 and cos(\pi), in effect, are separated- they are multiplied), you don't have to find the general solution to answer (b)!
 
i don't know much but i do know that u need to get your basics right. come see the lastest post in my blog. the web link may be of help
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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