SOLUTION: I have been working on this for 2 days, I just do not get it. Any help would be greatly appreciated. given f(x)=-x^3+2x^2+2x+5 find f(-1), f(0), and f(1)

Algebra ->  Linear-equations -> SOLUTION: I have been working on this for 2 days, I just do not get it. Any help would be greatly appreciated. given f(x)=-x^3+2x^2+2x+5 find f(-1), f(0), and f(1)       Log On


   

Question 5077: I have been working on this for 2 days, I just do not get it. Any help would be greatly appreciated.
given f(x)=-x^3+2x^2+2x+5
find
f(-1), f(0), and f(1)
Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
given f%28x%29=-x%5E3%2B2x%5E2%2B2x%2B5 find f(-1), f(0), and f(1).

Functions are very straight forward, but a lot of student freak out. They are basically just a more professional approach of writing equations...basically.

f(x) = 2x + 1 means there is an equation (function) and you do what it tells you to do (the right hand side) to the value x (the thing in the bracket)

So, in this example, it says..take x, mutliply it by 2 and then add 1.

So, for your example: f%28x%29=-x%5E3%2B2x%5E2%2B2x%2B5
f(-1) says, put in the value of -1 everywhere instead of x..so do it:

f%28-1%29+=+-%28-1%29%5E3+%2B+2%28-1%29%5E2+%2B+2%28-1%29+%2B+5
f%28-1%29+=+-%28-1%29+%2B+2%28%2B1%29+-+2+%2B+5
f%28-1%29+=+%2B1+%2B+2+-+2+%2B+5
f(-1) = +6

f(0) says, put in the value of 0 everywhere instead of x..so do it:

f%280%29+=+-%280%29%5E3+%2B+2%280%29%5E2+%2B+2%280%29+%2B+5
f%280%29+=+0+%2B+0+%2B+0+%2B+5
f(0) = +5

you try the f(1) yourself.

jon.