USE THE GRAPH TO FIND THE INDICATED FUNCTION VALUES

Use the graph of the function to find the indicated function values.

Problem 1 :

a) f(-2)        b) f(-1)        c) f(1/2)         d) f(1)

Solution:

a) f(-2)

Step 1 :

Draw a vertical line through -2 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = -2 and the graph of f(x).

So, the value of the function f(x) at x = -2 is 0.

f(-2) = 0

b) f(-1)

Step 1 :

Draw a vertical line through -1 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = -1 and the graph of f(x).

So, the value of the function f(x) at x = -1 is -2.

f(-1) = -2

c) f(1/2)

Step 1 :

Draw a vertical line through 1/2 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = 1/2 and the graph of f(x).

So, the value of the function f(x) at x = 1/2 is 0.

f(1/2) = 0

c) f(1)

Step 1 :

Draw a vertical line through 1 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = 1 and the graph of f(x).

So, the value of the function f(x) at x = 1 is -3.

f(1) = -3

Problem 2 :

a) f(-1)         b) f(2)            c) f(0)          d) f(1)

Solution:

a) f(-1) 

Step 1 :

Draw a vertical line through -1 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = -1 and the graph of f(x).

So, the value of the function f(x) at x = -1 is 4.

f(-1) = 4

b) f(2) 

Step 1 :

Draw a vertical line through 2 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = 2 and the graph of f(x).

So, the value of the function f(x) at x = 2 is 4.

f(2) = 4

c) f(0) 

Step 1 :

Draw a vertical line through 0 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = 0 and the graph of f(x).

So, the value of the function f(0) at x = 0 is 2.

f(0) = 2

d) f(1) 

Step 1 :

Draw a vertical line through 1 on the x-axis.

Step 2 :

Mark the point of intersection of the vertical line x = 1 and the graph of f(x).

So, the value of the function f(0) at x = 1 is 0.

f(1) = 0

Problem 3 :

a) f(-2)         b) f(1)              c) f(0)          d) f(2)

Solution:

a) f(-2) = -3        b) f(1) = 0        c) f(0) = 1          d) f(2) = 3

Problem 4 :

a) f(2)     b) f(1)       c) f(3)     d) f(-1)

Solution:

a) f(2) = 0         b) f(1) = undefined

c) f(3) = 1         d) f(-1) = 3