Question

Determine the exact equation of the function given: f(x)=k(x-1)(x+2) and goes thru point (2,-8)

Answer 1

I'm looking through my notes, and it gives info SO close to what I want...

Answer 2

-8 =k(2-1)(2+2)
-8 = k (1)(4)
-8= 4k
k=-2

Answer 3

So all I do was sub in values? Ok. Thank you.

Answer 4

Yes. You may need to multiply out the factors and express the answer in polynomial form. Check the directions.

Answer 5

"Multiply out"? And what do you mean by polynomial form?

Answer 6

He's saying that polynormial form is http://en.wikipedia.org/wiki/Polynomial - e.g. ax^2 + bx + c - basically the opposite of factored. really depends on how they want the final format of the equation

Answer 7

e.g. if k = -2, then one way to write the equation is f(x) = -2(x-1)(x+2)

Answer 8

another way is to FOIL (x-1)(x+2) to put the final equation in polynomial form

Answer 9

Ok. Thank you Chris.

Answer 10

Basically it's up to convention - they are equivalent

Answer 11

np!