# Bernoulli equation

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An ordinary first-order differential equation

$$a_0(x)y'+a_1(x)y=f(x)y^\alpha,$$

where $\alpha$ is a real number other than zero or one. This equation was first studied by J. Bernoulli [1]. The substitution $y^{1-\alpha}=z$ converts the Bernoulli equation to a linear inhomogeneous first-order equation, [2]. If $\alpha>0$, the solution of the Bernoulli equation is $y\equiv0$; if $0<\alpha<1$, at some points the solution is no longer single-valued. Equations of the type

$$[f(y)x+g(y)x^\alpha]y'=h(y),\quad\alpha\neq0,1,$$

are also Bernoulli equations if $y$ is considered as the independent variable, while $x$ is an unknown function of $y$.

#### References

 [1] J. Bernoulli, Acta Erud. (1695) pp. 59–67; 537–557 [2] E. Kamke, "Differentialgleichungen: Lösungen und Lösungsmethoden" , 1. Gewöhnliche Differentialgleichungen , Chelsea, reprint (1971)