SOLUTION: I need a little help trying to figure out this proble it is on how to find specified values of functions.. So here is my question.. Find f(2) given f(x) = -2x to the third power +

Algebra ->  Functions -> SOLUTION: I need a little help trying to figure out this proble it is on how to find specified values of functions.. So here is my question.. Find f(2) given f(x) = -2x to the third power +      Log On


   

Question 171311: I need a little help trying to figure out this proble it is on how to find specified values of functions.. So here is my question..
Find f(2) given f(x) = -2x to the third power + x two the second power +23 That is my question...
Found 4 solutions by KnightOwlTutor, jim_thompson5910, gonzo, solver91311:
Answer by KnightOwlTutor(293) About Me  (Show Source):
You can put this solution on YOUR website!
Replace x with 2
-2(2)^3+2^2+23=-2(8)+4+23=-16+27=11

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

f%28x%29=-2x%5E3%2Bx%5E2%2B23 Start with the given equation.


f%282%29=-2%282%29%5E3%2B%282%29%5E2%2B23 Plug in x=2.


f%282%29=-2%288%29%2B%282%29%5E2%2B23 Cube 2 to get 8.


f%282%29=-2%288%29%2B4%2B23 Square 2 to get 4.


f%282%29=-16%2B4%2B23 Multiply -2 and 8 to get -16.


f%282%29=11 Combine like terms.


So the answer is f%282%29=11.

Answer by gonzo(654) About Me  (Show Source):
You can put this solution on YOUR website!
f(x) = -2%2Ax%5E3+%2B+x%5E2+%2B+23
is what i think you said.
no matter.
the procedure is the same.
if
f(x) = -2%2Ax%5E3+%2B+x%5E2+%2B+23
then,
in order to find f(2), you have to substitute (2) for (x) in the equation.
your equation starts out as:
f(x) = -2%2Ax%5E3+%2B+x%5E2+%2B+23
you substitute (2) for (x) to get:
f(2) = -2%2A%282%29%5E3+%2B+%282%29%5E2+%2B+23
simplify:
f(2) = -2%2A%288%29+%2B+4+%2B+23
f(2) = -16+%2B+4+%2B+23
f(2) = 11
-----
if i didn't get your equation right, just follow the same procedure and you'll get your answer.
-----

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
Replace x with 2 everywhere it appears in your function and then do the arithmetic.