# Evaluating functions

4 videos

2 skills

Learn how to find the value of a function for a given input value.

### What is a function?

VIDEO
7:57 minutes

Functions assign a single unique output for each of their inputs. In this video, Sal gives many examples of various kinds of functions.

### How to evaluate a function given its formula (example)

VIDEO
0:59 minutes

Sal evaluates f(x)=49-x^2 at x=5.

### How to evaluate a function given its graph (example)

VIDEO
0:44 minutes

Sal evaluates a function at x=-1 using the graph of that function.

### Evaluating functions

PRACTICE PROBLEMS

Evaluate functions at a specific input value, given either the functions' formula or their graph.

### How to evaluate an expression that contains function notation (example)

VIDEO
1:23 minutes

Sal evaluates -2*f(-6)+g(1) given the graphs of f and g.

### Evaluating function expressions

PRACTICE PROBLEMS

Evaluate expressions that contain function notation, given the functions' graphs.