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
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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