How to Calculate FXY Partial Derivatives

Partial derivatives are an important concept in multivariate calculus.
••• Comstock Images/Comstock/Getty Images

Partial derivatives in calculus are derivatives of multivariate functions taken with respect to only one variable in the function, treating other variables as though they were constants. Repeated derivatives of a function f(x,y) may be taken with respect to the same variable, yielding derivatives Fxx and Fxxx, or by taking the derivative with respect to a different variable, yielding derivatives Fxy, Fxyx, Fxyy, etc. Partial derivatives are typically independent of the order of differentiation, meaning Fxy = Fyx.

    Calculate the derivative of the function f(x,y) with respect to x by determining d/dx (f(x,y)), treating y as if it were a constant. Use the product rule and/or chain rule if necessary. For example, the first partial derivative Fx of the function f(x,y) = 3x^2*y - 2xy is 6xy - 2y.

    Calculate the derivative of the function with respect to y by determining d/dy (Fx), treating x as if it were a constant. In the above example, the partial derivative Fxy of 6xy - 2y is equal to 6x - 2.

    Verify that the partial derivative Fxy is correct by calculating its equivalent, Fyx, taking the derivatives in the opposite order (d/dy first, then d/dx). In the above example, the derivative d/dy of the function f(x,y) = 3x^2*y - 2xy is 3x^2 - 2x. The derivative d/dx of 3x^2 - 2x is 6x - 2, so the partial derivative Fyx is identical to the partial derivative Fxy.

Related Articles

How to Differentiate a Function
How to Solve for a Variable in a Trig Function
How to Differentiate Negative Exponentials
How to Calculate a Tangent
How to Find the X Intercept of a Function
What Are Reciprocal Identities?
How to Calculate Solubilities
How to Find the Slope of a Nonlinear Line
How to Find Equations of Tangent Lines
How to Integrate Sin^2 X
Associative & Commutative Properties of Multiplication
How to Calculate Keq Given pKa
How to Find a Tangent Line to a Curve
How to Calculate a Horizontal Tangent Line
Endpoint Math Formula
To Calculate Arcsine, What Buttons Do You Press on...
How to Evaluate Trig Functions Without a Calculator
How to Simplify Exponents
How to Find a Fraction of a Number

Dont Go!

We Have More Great Sciencing Articles!