How can the Intermediate Value Theorem be used to find a root of a polynomial?

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Hey i was jus wondering how to solve this equation i need to find a value of x when subsituted in the eqn is less than 0 so a negative value and a value of x when substituted into the eqn is greater than 0 so a positive value
this will prove that a root exists between those domains (ie. Intermediate value theorm)

p(x)=60x(1+x)^72-(1+x)^72+1

Thankz for the help
 
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if you're trying to test for a # greater/less than 0, just set your equation equal to 0 and solve for x. then choose values greater/less than the value you found.
 
hey yea that's wa i was plannin on doing but since its like ^72 i can't figure that part out
 
Just by staring at p(x) you can tell one root. Can you guess?
 
is it 0 -1 or 1
 
Whcih do you think?
 
hmmm ill go with -1 ?
 
Okay, plug in x = -1. What do you get?
 
"middle-term"
 
  • #10
i got a value of 1
 
  • #11
which is greater than 0 so now i need to find a value where f(x)<0
 
  • #12
any ideas?
 
  • #13
I'd try the next integers to either side.
 
  • #14
when i tried 2 , 3 and four i got really large numbers
 
  • #15
You are not paying attention to the polynomial's terms.
 
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