Factoring Equations with Real Roots

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Benzoate
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Homework Statement



Not sure how to factor this equation:

x^4-x^3-x^2+4=0
btw , I do not have a TI 83 calculator
 
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lol this isn't a simple equation to factor its a 4 exponent polynomial, good luck with that, but there is a method i learn in college, don't remember though
 
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 don't know =(
 
observe the degradation in powers carefully...
 
It doesn't have any real factors, since:
[tex]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[/tex]
:)
 
But every real quartic equation has real quadratic factors (because the complex roots come in conjugate pairs):

(x² + ax + b)(x² + cx + d) :smile:
 
uhm didnt know that! but i mistyped a little, i meant real roots, not real factors.