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#1 2007-09-17 21:31:29
- Luke Wilson
- Guest
Please Help!
There are 2 solutions for -x^5 - x^4 + x^2 =0. One is zero. How to find the other one without graphing?
#2 2007-09-18 07:45:43
- John E. Franklin
- Member
- Registered: 2005-08-29
- Posts: 3,588
Re: Please Help!
Not to hard to get an estimate without graphing.
First pull out the minus x squared.
Then you get x^3 + x^2 = 1 .
So just guessing x = 1/2, that is about 1/8 + 1/4, woops too small.
Guess higher but below 1 because they go down with power.
Guess x = 2/3, that is 8/27 + 4/9, woops still too small.
Guess x = 3/4, that is 27/64 + 9/16, YeeHahh!! Almost Perfect!!!
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