Implicit Differentiation Calculator with Steps
Calculate implicit derivatives step by step
The implicit differentiation calculator will find the first and second derivatives of an implicit function treating either $$$y$$$ as a function of $$$x$$$ or $$$x$$$ as a function of $$$y$$$, with steps shown.
Your Input
Find $$$\frac{d}{dx} \left(x^{3} + y^{3} = 2 x y\right)$$$.
Solution
Differentiate separately both sides of the equation (treat $$$y$$$ as a function of $$$x$$$): $$$\frac{d}{dx} \left(x^{3} + y^{3}{\left(x \right)}\right) = \frac{d}{dx} \left(2 x y{\left(x \right)}\right)$$$.
Differentiate the LHS of the equation.
The derivative of a sum/difference is the sum/difference of derivatives:
$${\color{red}\left(\frac{d}{dx} \left(x^{3} + y^{3}{\left(x \right)}\right)\right)} = {\color{red}\left(\frac{d}{dx} \left(x^{3}\right) + \frac{d}{dx} \left(y^{3}{\left(x \right)}\right)\right)}$$The function $$$y^{3}{\left(x \right)}$$$ is the composition $$$f{\left(g{\left(x \right)} \right)}$$$ of two functions $$$f{\left(u \right)} = u^{3}$$$ and $$$g{\left(x \right)} = y{\left(x \right)}$$$.
Apply the chain rule $$$\frac{d}{dx} \left(f{\left(g{\left(x \right)} \right)}\right) = \frac{d}{du} \left(f{\left(u \right)}\right) \frac{d}{dx} \left(g{\left(x \right)}\right)$$$:
$${\color{red}\left(\frac{d}{dx} \left(y^{3}{\left(x \right)}\right)\right)} + \frac{d}{dx} \left(x^{3}\right) = {\color{red}\left(\frac{d}{du} \left(u^{3}\right) \frac{d}{dx} \left(y{\left(x \right)}\right)\right)} + \frac{d}{dx} \left(x^{3}\right)$$Apply the power rule $$$\frac{d}{du} \left(u^{n}\right) = n u^{n - 1}$$$ with $$$n = 3$$$:
$${\color{red}\left(\frac{d}{du} \left(u^{3}\right)\right)} \frac{d}{dx} \left(y{\left(x \right)}\right) + \frac{d}{dx} \left(x^{3}\right) = {\color{red}\left(3 u^{2}\right)} \frac{d}{dx} \left(y{\left(x \right)}\right) + \frac{d}{dx} \left(x^{3}\right)$$Return to the old variable:
$$3 {\color{red}\left(u\right)}^{2} \frac{d}{dx} \left(y{\left(x \right)}\right) + \frac{d}{dx} \left(x^{3}\right) = 3 {\color{red}\left(y{\left(x \right)}\right)}^{2} \frac{d}{dx} \left(y{\left(x \right)}\right) + \frac{d}{dx} \left(x^{3}\right)$$Apply the power rule $$$\frac{d}{dx} \left(x^{n}\right) = n x^{n - 1}$$$ with $$$n = 3$$$:
$$3 y^{2}{\left(x \right)} \frac{d}{dx} \left(y{\left(x \right)}\right) + {\color{red}\left(\frac{d}{dx} \left(x^{3}\right)\right)} = 3 y^{2}{\left(x \right)} \frac{d}{dx} \left(y{\left(x \right)}\right) + {\color{red}\left(3 x^{2}\right)}$$Thus, $$$\frac{d}{dx} \left(x^{3} + y^{3}{\left(x \right)}\right) = 3 x^{2} + 3 y^{2}{\left(x \right)} \frac{d}{dx} \left(y{\left(x \right)}\right)$$$.
Differentiate the RHS of the equation.
Apply the constant multiple rule $$$\frac{d}{dx} \left(c f{\left(x \right)}\right) = c \frac{d}{dx} \left(f{\left(x \right)}\right)$$$ with $$$c = 2$$$ and $$$f{\left(x \right)} = x y{\left(x \right)}$$$:
$${\color{red}\left(\frac{d}{dx} \left(2 x y{\left(x \right)}\right)\right)} = {\color{red}\left(2 \frac{d}{dx} \left(x y{\left(x \right)}\right)\right)}$$Apply the product rule $$$\frac{d}{dx} \left(f{\left(x \right)} g{\left(x \right)}\right) = \frac{d}{dx} \left(f{\left(x \right)}\right) g{\left(x \right)} + f{\left(x \right)} \frac{d}{dx} \left(g{\left(x \right)}\right)$$$ with $$$f{\left(x \right)} = x$$$ and $$$g{\left(x \right)} = y{\left(x \right)}$$$:
$$2 {\color{red}\left(\frac{d}{dx} \left(x y{\left(x \right)}\right)\right)} = 2 {\color{red}\left(\frac{d}{dx} \left(x\right) y{\left(x \right)} + x \frac{d}{dx} \left(y{\left(x \right)}\right)\right)}$$Apply the power rule $$$\frac{d}{dx} \left(x^{n}\right) = n x^{n - 1}$$$ with $$$n = 1$$$, in other words, $$$\frac{d}{dx} \left(x\right) = 1$$$:
$$2 x \frac{d}{dx} \left(y{\left(x \right)}\right) + 2 y{\left(x \right)} {\color{red}\left(\frac{d}{dx} \left(x\right)\right)} = 2 x \frac{d}{dx} \left(y{\left(x \right)}\right) + 2 y{\left(x \right)} {\color{red}\left(1\right)}$$Thus, $$$\frac{d}{dx} \left(2 x y{\left(x \right)}\right) = 2 x \frac{d}{dx} \left(y{\left(x \right)}\right) + 2 y{\left(x \right)}$$$.
Therefore, we have obtained the following linear equation with respect to the derivative: $$$3 x^{2} + 3 y^{2} \frac{dy}{dx} = 2 x \frac{dy}{dx} + 2 y$$$.
Solving it, we obtain that $$$\frac{dy}{dx} = \frac{3 x^{2} - 2 y}{2 x - 3 y^{2}}$$$.