# Directional Derivative

Find the directional derivative of f(x,y) = 2x^3-y^2+xy at the point (1,2) in the direction of the vector

(1,3). Be careful: That direction vector isn't a unit vector!

https://brainmass.com/math/derivatives/directional-derivative-18496

#### Solution Summary

Gradients are used to find a directional vector. The solution is well presented.

$2.49