Question

2

f(x) = x + 2 x + 3.
Answer the following three questions about the values f assigns using the instructions above. Do not include an equals sign or the letter f in y
your answers, click the Save Answer button.
1.
What is the value of f(3)?
Enter Your Unsimplified Answer Here: (3^2)+2(3)+3
Enter Your Simplified Answer Here: 18
What is the value of f(4x)?
Enter Your Unsimplified Answer Here:
Enter Your Simplified Answer Here:
What is the value of f( x-3)?
Enter Your Unsimplified Answer Here:
Enter Your Simplified Answer Here:
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Answer 1

f(4x) = (4x)^2 +2(4x) +3 = 16x^2 +8x +3

f(x-3) = (x-3)^2 +2(x-3) +3 = x^2 -4x +6

Explanation:

Apparently, you want to evaluate ...

• f(4x)
• f(x-3)

for f(x) = x^2 +2x +3.

Put the given argument values in place of the function variable and do the math.

f(4x)

f(4x) = (4x)^2 +2(4x) +3

= 16x^2 +8x +3

__

f(x-3)

f(x-3) = (x-3)^2 +2(x-3) +3

= x^2 -6x +9 +2x -6 +3 = x^2 -4x +6