Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
How to sketch the graph of f(x)=x^2(x^24) including the inflection point?
 2 years ago
 2 years ago
How to sketch the graph of f(x)=x^2(x^24) including the inflection point?
 2 years ago
 2 years ago

This Question is Closed

satellite73Best ResponseYou've already chosen the best response.2
start with \[y=x^2(x2)(x+2)\] so you see that you have 3 zeros, at x =2,x=0,x=2
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
the zero at x = 0 has multiplicity 2, so the graph will touch the x  axis there but not cross it
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
to find the point of inflection you need the second derivative, \[f(x)=x^44x^2\] \[f'(x)=4x^38x\] \[f''(x)=12x^28\] set equal to zero and solve
 2 years ago

SBest ResponseYou've already chosen the best response.0
My main question is that, when i find the inflection point I put square root of 2/3 into the original formula and i get 20/3 right?
 2 years ago

SBest ResponseYou've already chosen the best response.0
And this point can not be on the graph, this makes me confused
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
yes, for the second coordinate you evaluate the function at \[\sqrt{\frac{2}{3}}\]
 2 years ago

SBest ResponseYou've already chosen the best response.0
yes, so I should get 2 inflection points
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
it must be on the graph, plug in the x, find the y
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
right \[\pm\sqrt{\frac{2}{3}}\]
 2 years ago

faznaBest ResponseYou've already chosen the best response.0
for point of inflection we need only to equate first derivative of f(x) to 0.not the second
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
actually it is the second first derivative gives relative max or min
 2 years ago

SBest ResponseYou've already chosen the best response.0
it should be plugged in the original formula, right?
 2 years ago

satellite73Best ResponseYou've already chosen the best response.2
yes, original function you have the x, you want the y
 2 years ago

SBest ResponseYou've already chosen the best response.0
But in the end my inflection point comes up to be ( square root of 2/3 ;  20/3) and (square root of 2/3 ;  20/3) and my minimum points are (2;4) and (2;4) and it seems that the point of inflection cant be on the graph
 2 years ago

faznaBest ResponseYou've already chosen the best response.0
but im sure that i can get the points of inflection from first derivative,not the second
 2 years ago
See more questions >>>
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.