(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Show [itex]f(x) = x^3-x^2+x-1[/itex] is never decreasing.

2. The attempt at a solution

[itex]f(x) = x^3-x^2+x-1[/itex]

[itex]f'(x) = 3x^2 - 2x + 1[/itex]

[itex]f''(x) = 6x - 2[/itex]

3. The problem that I'm facing

I don't understand what it means by never decreasing. Do I say that when differentiates, it gives a positive quadratic equation hence it never decreasing or when differentiated twice, it forms a positive linear equation hence never decreasing?

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# How to show that f(x) = x^3 - x^2 + x - 1 is never decreasing

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