PLEASE Calculus Help?

(a) find the critical numbers of f (if any), (b) find the open interval(s) on which the function is increasing or decreasing, (c) apply the First Derivative Test to identify all relative extrema, and (d) use a graphing utility to confirm your
results .

1. f(x)=x^3-6x^2+15
2. f(x)= x/x+1

Question

PLEASE Calculus Help?

(a) find the critical numbers of f (if any),  (b) find the open interval(s) on which the function is increasing  or decreasing, (c) apply the First Derivative Test to identify all  relative extrema, and (d) use a graphing utility to confirm your
results .

1.  f(x)=x^3-6x^2+15
2. f(x)= x/x+1

aggie12341 · Answer

1. 5^
2. 43^4

anonymous · Answer

@aggie12341 Can you please explain?

anonymous · Answer

I don't understand the answers aggie put up?

anonymous · Answer

and honestly I don't know how to solve this. I do online schooling and don't understand half the material...

anonymous · Answer

@Loser66 could you please help?

anonymous · Answer

@satellite73

loser66 · Answer

for 1/ derivative of f =?

anonymous · Answer

you mean the derivative of 1.  f(x)=x^3-6x^2+15?

loser66 · Answer

yes

anonymous · Answer

(x^3−6x^2+15)
=(x^3)−6(x^2)
=3x^2−6⋅2x
=3x^2−12x

anonymous · Answer

did I do it right?

loser66 · Answer

correct, now, label it, it is f'(x) = 3x^2 -12x 
find the roots of f'(x), I mean f'(x) =0 when x =??

anonymous · Answer

I am not sure how to find them. I tried moving the 3x^2 to the left side, dividing by 3 and so on. but I'm pretty I'm not getting the right answer

loser66 · Answer

factor x out

loser66 · Answer

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