Show that the equation x^3-12x-7.2=0 has one positive and two negative roots:(adsbygoogle = window.adsbygoogle || []).push({});

I know this can be solved by trial and error, and finding f(0),f(1-4),f(-1 - -4) I have shown that It has two negative roots and one positive however I'm wondering if there is another method on how to show it has two negative and one positive root? I've found the max and min points but im not sure what to do from there...

thanks

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# Homework Help: Showing one positive and two neg roots

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