Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
giggles123
Group Title
let f(x)=ax^3+6x^2+bx+4. Determine the constant a and b such that f has a relative min at x=1 and a rel max at x=2@Algebra
 2 years ago
 2 years ago
giggles123 Group Title
let f(x)=ax^3+6x^2+bx+4. Determine the constant a and b such that f has a relative min at x=1 and a rel max at x=2@Algebra
 2 years ago
 2 years ago

This Question is Closed

moneybird Group TitleBest ResponseYou've already chosen the best response.2
first derivative of f(x) first
 2 years ago

giggles123 Group TitleBest ResponseYou've already chosen the best response.0
I did that then what? I got F'(x)=3ax^2+12x+b
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[f'(x)=3a^2+12x+b\] \[f'(1)=0 ;f'(2)=0\]
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[f'(x)=3ax^2+12x+b*\]
 2 years ago

Hero Group TitleBest ResponseYou've already chosen the best response.0
I was just about to say....what happened to the x?
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[f'(1)=3a12+b=0\]
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[f'(2)=3a(4)+12(2)+b=0\]
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[3a+b=12\] \[12a+b=24\]
 2 years ago

moneybird Group TitleBest ResponseYou've already chosen the best response.2
3a + b =12 12a + 24 +b = 0 12a + b =24 (3a + b) = 12 9a = 36 a = 4 b =24
 2 years ago

giggles123 Group TitleBest ResponseYou've already chosen the best response.0
what happened to the x?
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[ 3a+b=12\] \[(12a+b=24)\]  9a+0b=36 9a=36 a=4 12+b=12 b=24 gj money
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
what do you mean what happen to x?
 2 years ago

giggles123 Group TitleBest ResponseYou've already chosen the best response.0
how did you go from f'(x)=3ax^2+12x+b* to f′(−1)=3a−12+b=0
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
\[f(a)=4x^3+6x^2+24x+4\]
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
1 and 2 are critical numbers this is a polynomial so our critical numbers only exist when f'=0
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
f'(1)=0 f'(2)=0
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
this was given to us
 2 years ago

myininaya Group TitleBest ResponseYou've already chosen the best response.1
money and i applied these conditions to f'
 2 years ago

giggles123 Group TitleBest ResponseYou've already chosen the best response.0
I got it. Thank you so much!
 2 years ago

luckey Group TitleBest ResponseYou've already chosen the best response.0
here b can take any value and a is rrestricted to any value in the interval (2,2)
 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.