# What is a derivative in calculus for dummies?

## What is a derivative in calculus for dummies?

The derivative of a function tells you how fast the output variable (like y) is changing compared to the input variable (like x). For example, if y is increasing 3 times as fast as x — like with the line y = 3x + 5 — then you say that the derivative of y with respect to x equals 3, and you write.

## What are the basic rules for derivatives?

The Derivative tells us the slope of a function at any point. There are rules we can follow to find many derivatives. For example: The slope of a constant value (like 3) is always 0….Derivative Rules.

Common Functions Function Derivative
Power Rule xn nxn−1
Sum Rule f + g f’ + g’
Difference Rule f – g f’ − g’
Product Rule fg f g’ + f’ g

Why do we need derivatives calculus?

Derivatives are used to find the rate of changes of a quantity with respect to the other quantity. The equation of tangent and normal line to a curve of a function can be calculated by using the derivatives. Derivative of a function can be used to find the linear approximation of a function at a given value.

### What are the derivative formulas?

General Derivative Formulas:

• ddx(c)=0 where c is any constant.
• ddxxn=nxn–1 is called the Power Rule of Derivatives.
• ddxx=1.
• ddx[f(x)]n=n[f(x)]n–1ddxf(x) is the Power Rule for Functions.
• ddx√x=12√x.
• ddx√f(x)=12√f(x)ddxf(x)=12√f(x)f′(x)
• ddxc⋅f(x)=cddxf(x)=c⋅f′(x)

### Do you learn derivatives in pre calc?

Precalculus is designed to prepare you for more challenging math courses. Precalculus introduces to you the concepts that you will be learning about in further classes. You will be learning about limits and derivatives for the most part.