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Benzoate
Apr12-08, 06:11 PM
1. The problem statement, all variables and given/known data

Not sure how to factor this equation:

x^4-x^3-x^2+4=0
btw , I do not have a TI 83 calculator

th3plan
Apr12-08, 09:56 PM
lol this isnt a simple equation to factor its a 4 exponent polynomial, good luck with that, but there is a method i learn in college, dont remember though

RyanSchw
Apr12-08, 10:22 PM
I'd be curious to know this as well; if I had to guess I’d say that is has no factors given that the graph never crosses the x-axis. I dunno =(

physixguru
Apr13-08, 01:16 AM
observe the degradation in powers carefully...

Kurret
Apr13-08, 05:20 AM
It doesnt have any real factors, since:
x^4-x^3-x^2+4=(x^2-\frac{x}{2}-\frac{6}{8})^2+~(\frac{x}{2}-\frac{6}{8})^2+\frac{184}{64} > 0
:)

tiny-tim
Apr13-08, 06:44 AM
But every real quartic equation has real quadratic factors (because the complex roots come in conjugate pairs):

(x² + ax + b)(x² + cx + d) :smile:

Kurret
Apr13-08, 06:48 AM
uhm didnt know that! but i mistyped a little, i meant real roots, not real factors.