# Derivative Approximation

Approximate the derivative of y=x^3 at x=2 by assuming delta x = 0.001 and determining the corresponding change delta y. Compare the approximate value with the exact value.

This is what I did - does it look at all right?

y(2)=(2)^3=8

y(2.01)=(2.01)^3=8.120601

delta y=8.120601-8=0.120601

dy/dx~delta y/delta x = 0.120601/0.001=120.601

https://brainmass.com/math/derivatives/derivative-approximation-exact-value-function-20599

#### Solution Preview

dy/dx = 3x^2

or dy = 3x^2 * dx

dy = 3*2^2 * .001

dy = .012 ( ...

#### Solution Summary

A derivative is approximated and compared to its exact value. The approximate value with the exact value is compared.

$2.49