xy + x + y = x^2y^2
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(x dy/dx + y) + 1 + dy/dx = x^2 2y dy/dx + 2x y^2
(x+1) dy/dx + (y+1) = 2 y x^2 dy/dx + 2x y^2
(x+1 - 2y x^2) dy/dx = 2x y^2 - (y+1)
dy / dx = (2x y^2 - y - 1) / (x + 1 - 2yx^2)
(x+1) dy/dx + (y+1) = 2 y x^2 dy/dx + 2x y^2
(x+1 - 2y x^2) dy/dx = 2x y^2 - (y+1)
dy / dx = (2x y^2 - y - 1) / (x + 1 - 2yx^2)
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For problems like this, just multiply both sides by d/dx
d/dx(xy+x+y)=d/dx(x^2y^2)
x*y'+y'+y+1=2x^2y*y'+2xy^2
Just factor and divide
y'(x) = (-2 x y^2+y+1)/(2 x^2 y-x-1)
In general, if you have to do differentiation, you can use Wolfram Alpha, its software is good enough to
take in requests like "xy + x + y = x^2y^2, dy/dx=".
it will give you the answer, and show you step by step how it got there using the basic rules of calculus
d/dx(xy+x+y)=d/dx(x^2y^2)
x*y'+y'+y+1=2x^2y*y'+2xy^2
Just factor and divide
y'(x) = (-2 x y^2+y+1)/(2 x^2 y-x-1)
In general, if you have to do differentiation, you can use Wolfram Alpha, its software is good enough to
take in requests like "xy + x + y = x^2y^2, dy/dx=".
it will give you the answer, and show you step by step how it got there using the basic rules of calculus
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[1∙y + x∙(dy/dx)] + 1 + (dy/dx) = [2x∙y² + x²∙(2y)(dy/dx)]
y + x(dy/dx) + 1 + (dy/dx) = 2xy² + 2x²y(dy/dx)
(dy/dx)[x + 1 - 2x²y] = 2xy² - y - 1
dy/dx = [2xy² - y - 1] / [1 + x - 2x²y]
Or you could do:
g(x,y) = h(x,y)
f(x,y) = h(x,y) - g(x,y)
dy/dx = -- fx(x,y) / fy(x,y)
y + x(dy/dx) + 1 + (dy/dx) = 2xy² + 2x²y(dy/dx)
(dy/dx)[x + 1 - 2x²y] = 2xy² - y - 1
dy/dx = [2xy² - y - 1] / [1 + x - 2x²y]
Or you could do:
g(x,y) = h(x,y)
f(x,y) = h(x,y) - g(x,y)
dy/dx = -- fx(x,y) / fy(x,y)
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Differentiating implicitly:
xy' + y + 1 + y' = 2(xy)(xy' + y)
solve for y'.
xy' + y + 1 + y' = 2(xy)(xy' + y)
solve for y'.