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Increasing function (1 Viewer)

machine2035

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Guessing it has something to do with f'(x) > 0 ?

I got as far as finding f'(x) and thats it.

Cheers.
 

Carrotsticks

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We indeed want f'(x) > 0, for all x.

So we differentiate f(x) (we get a quadratic), then let the discriminant be less than zero. By doing this, you always have the quadratic being positive and hence f'(x) > 0.
 

machine2035

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We indeed want f'(x) > 0, for all x.

So we differentiate f(x) (we get a quadratic), then let the discriminant be less than zero. By doing this, you always have the quadratic being positive and hence f'(x) > 0.
Awesome, cheers.

Ended up getting k < 3
 

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