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Find f(-1) when f(x) = 4x^2 + 4x + 1.

User Arif Eqbal
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1 Answer

20 votes
20 votes

Answer:

f(-1) = 1

Explanation:

What is a function?

A function is a relation that has a set of inputs which have corresponding outputs.

How function notation is written f(x) = 2x

Where

  • f = name of function
  • (x) = input of function
  • the "x" at 2x = what the function does , in other words where you plug in the input at.

Finding f(-1)

Here we have the given function f(x) = 4x² + 4x + 1

We want to find f(-1) ( or the output when the input is -1 )

To do so we replace all of the "x"'s in the function with the input or -1

So f(-1) = 4x² + 4x + 1

==> replace all x's with "-1"

f(-1) = 4(-1)² + 4(-1) + 1

==> evaluate exponent

f(-1) = 4(1) + 4(-1) + 1

==> multiply 4 and 1

f(-1) = 4 + 4(-1) + 1

==> multiply 4 and -1

f(-1) = 4 - 4 + 1

==> subtract 4 from 4

f(-1) = 1

And we are done!

User Scottie
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3.2k points