Rewrite equation: Rewrite the differential equation in a more simplified form by dividing both sides by 2.dxdy=x+y2x+2y+21
Integrating factor: Notice that the equation is not separable as is, so we look for an integrating factor or a substitution that can simplify it. Let's try the substitution u=x+y.
Find dxdu: Differentiate u with respect to x to find dxdu. dxdu=dxdx+dxdy dxdu=1+dxdy
Substitute dxdu: Substitute dxdy from the original equation into the dxdu equation.dxdu=1+2x+2yx+y+1
Rewrite with u: Since u=x+y, we can rewrite the equation as:dxdu=1+2uu+1
Simplify equation: Simplify the equation.dxdu=2u2u+u+1dxdu=2u3u+1
Separate variables: Separate variables to integrate.3u+12udu=dx
Integrate both sides: Integrate both sides.∫3u+12udu=∫dx
Partial fraction decomposition: Use partial fraction decomposition on the left side.Let 3u+12u=3u+1A, then 2u=A.A=2.
Integrate with A: Integrate using the determined A value.∫3u+12du=∫dx
Perform integration: Perform the integration. (32)ln∣3u+1∣=x+C
Solve for u: Solve for u by exponentiating both sides.|\(3u + 1| = e^{\frac{3}{2}(x + C)}|
Exponentiate both sides: Remove the absolute value by considering both positive and negative cases.3u+1=±e23(x+C)
Remove absolute value: Solve for u.u=3±e23(x+C)−1
Solve for u: Substitute back u=x+y.x+y=(±e23(x+C)−1)/3
Substitute back u: Solve for y.y=(±e23(x+C)−1)/3−x
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