A third degree polynomial function f has real zeros -2, 1/2, and 3 and its leading coefficient negative. Write an equation for f. Sketch the graph of f. How many different polynomial functions are possible for f?

Question

anonymous · Answer

infinitely many

anonymous · Answer

if $-2$ is a zero, one factor is $x+2$

anonymous · Answer

if $\frac{1}{2}$ is a zero, one factor is $2x-1$

anonymous · Answer

guess what one factor is if $3$ is a zero?

anonymous · Answer

3-x?

anonymous · Answer

or $x-3$ either way

anonymous · Answer

How would I graph it? And what is the equation. Or how would
I figure that out?

anonymous · Answer

multiply it out $$(x+2)(2x-1)(3-x)$$

anonymous · Answer

Is that the inside outside thing?

anonymous · Answer

@satellite73

anonymous · Answer

i have no idea what "inside outside" thing means 
you can leave it like that, or multiply out

jim_thompson5910 · Answer

@j_slate123 you must be thinking of FOIL ?

anonymous · Answer

How would I multiply it out?

anonymous · Answer

if it was me, i would cheat to make sure i get it right

anonymous · Answer

Yes foil haha

anonymous · Answer

attachment

anonymous · Answer

http://www.wolframalpha.com/input/?i=%28x%2B2%29%282x-1%29%283-x%29

jim_thompson5910 · Answer

yeah I don't like FOIL either. The box method may be a better choice

anonymous · Answer

I don't see how to multiply it on there

jim_thompson5910 · Answer

are you familiar with the box method?

anonymous · Answer

No

jim_thompson5910 · Answer

it's a visual way to think of FOIL. It allows you to multiply more than just binomials though

jim_thompson5910 · Answer

let's say we want to multiply (x+2) and (2x+1)

we'd start with this set up

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