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Given the function f(x)=4x2−3x+4f(x)=4x2-3x+4. Calculate the following values:

f(−2)=f(-2)=
f(−1)=f(-1)=
f(0)=f(0)=
f(1)=f(1)=
f(2)=f(2)=

1 Answer

10 votes

Answer:

26, 11, 4, 5, 14

Explanation:

To find the value of the function, replace the variable with the number and do the arithmetic.

f(-2) = 4(-2)² -3(-2) +4 = 16 +6 +4 = 26

For doing repetitive calculations, it is convenient to write the formula into a calculator or spreadsheet and let it work from the list of values. That is what we did in the attached. It shows a table of x and f(x) for the values of x you are interested in.

The function values are ...

  • f(-2) = 26
  • f(-1) = 11
  • f(0) = 4
  • f(1) = 5
  • f(2) = 14

_____

Additional comment

For evaluating polynomials, either by hand or machine, it is often convenient to rewrite the polynomial in Horner Form. The total number of math operations tends to be reduced. When doing this by hand, the arithmetic tends to be easier.

f(x) = (4x -3)x +4

That is, the powers of x accumulate as each layer in parentheses is multiplied by x and the next coefficient added to the result.

Using this form, ...

f(-1) = (4(-1) -3)(-1) +4

f(-1) = (-7)(-1) +4 = 11

Given the function f(x)=4x2−3x+4f(x)=4x2-3x+4. Calculate the following values: f(−2)=f-example-1
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