Finding where f(x) = x + 9/x is increasing and decreasing

wr1015 · Oct 4, 2005

ok so in the problem f(x)= x + 9/x, I know how to write where f is increasing, but how do you write how it's decreasing? Is it written as [-3,0)U(0,3]? since x=0 is a vertical asymptote wouldn't all the x-values between -3 and 3 be as close to 0 as possible?

mathmike · Oct 4, 2005

wouldnt f(-3) = -3 + 9 / (-3) = -3 -3 = -6

wr1015 · Oct 4, 2005

mathmike said:

wouldnt f(-3) = -3 + 9 / (-3) = -3 -3 = -6

yeah that's my local min at (-3,-6).

Finding where f(x) = x + 9/x is increasing and decreasing

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Finding where f(x) = x + 9/x is increasing and decreasing

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