`dy/dx = (1-2x) / (4x-x^2)`
This differential equation is separable since it can be written in the form
`N(y)dy =M(x)dx`
Bringing together same variables on one side, the equation becomes
`dy=(1-2x)/(4x-x^2)dx`
Taking the integral of both sides, it turns into
`int dy = int(1-2x)/(4x-x^2)dx`
`y+C_1 = int(1-2x)/(4x-x^2)dx`
`y+C_1= int (1-2x)/(x(4-x))dx`
To take the integral of right side, apply partial fraction decomposition.
- `(1-2x)/(x(4-x)) = A/x + B/(4-x)`
`1-2x = A(4-x)+Bx`
Let x=0.
`1-2(0) = A(4-0)+B(0)`
`1=4A`
`1/4=A`
Let x=4.
`1-2(4)=A(4-4)+B(4)`
`-7=4B`
`-7/4=B`
- `1/(2x-x^2) = (1/4)/x + (-7/4)/(4-x)`
`1/(2x-x^2) = 1/(4x) + (-7)/(4(4-x))`
`1/(2x-x^2) = 1/(4x) + (-7)/(-4(x-4))`
`1/(2x-x^2) = 1/(4x) + (7)/(4(x-4))`
So the integrand at the right side decomposes to
`y + C_1 = int (1/(4x) + 7/(4(x-4)))dx`
Then, apply the formula `int 1/u du = ln|u| + C` .
`y + C_1 = 1/4ln|x| + 7/4ln|x-4|+C_2`
Isolating the y, the equation becomes
`y= 1/4ln|x| + 7/4ln|x-4|+C_2-C_1`
Since C1 and C2 represent any number, it can be expressed as a single constant C.
`y = 1/4ln|x| + 7/4ln|x-4|+C`
Therefore, the general solution of the given differential equation is `y = 1/4ln|x| + 7/4ln|x-4|+C` .
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