Solve this initial following
[(e^x cosy+2y)/siny]dy/dx + e^x = 0
[(e^x cosy+2y)/siny]dy/dx + e^x = 0
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The equation gives and exact differential form.
(e^x cos(y) + 2y) dy + e^x sin(y) dx = 0.
∂/∂y e^x sin(y) = e^x cos(y) = ∂/∂x (e^x cos(y) + 2y).
So all solutions are defined implicitly by f(x,y) = C where
∂f/∂x = e^x sin(y) and ∂f/∂y = e^x cos(y) + 2y.
Integrate the latter with respect to y.
f(x, y) = ∫ e^x cos(y) + 2y dy = e^x sin(y) + y² + g(x).
Then taking the partial with respect to x
∂f/∂x = e^x sin(y) = e^x sin(y) + g '(x) ==> g'(x) = 0.
So the solutions are defined by
e^x sin(y) + y² = C.
You can't back y out of this equation, but you could express x as a function of y by
x = ln[(C - y²) csc(y)].
(e^x cos(y) + 2y) dy + e^x sin(y) dx = 0.
∂/∂y e^x sin(y) = e^x cos(y) = ∂/∂x (e^x cos(y) + 2y).
So all solutions are defined implicitly by f(x,y) = C where
∂f/∂x = e^x sin(y) and ∂f/∂y = e^x cos(y) + 2y.
Integrate the latter with respect to y.
f(x, y) = ∫ e^x cos(y) + 2y dy = e^x sin(y) + y² + g(x).
Then taking the partial with respect to x
∂f/∂x = e^x sin(y) = e^x sin(y) + g '(x) ==> g'(x) = 0.
So the solutions are defined by
e^x sin(y) + y² = C.
You can't back y out of this equation, but you could express x as a function of y by
x = ln[(C - y²) csc(y)].