Need help on this curve-sketching problem.

  • Context: Undergrad 
  • Thread starter Thread starter jzq
  • Start date Start date
Click For Summary
SUMMARY

The discussion focuses on curve sketching for the function f(t) = 3t^4 + 4t^3. Key findings include the domain being all real numbers, x-intercepts at (0,0) and (-4/3), and a y-intercept at (0,0). The function has no asymptotes, with end behavior pointing up at both ends. The first derivative is f'(t) = 12t^3 + 12t^2, indicating decreasing behavior on (-∞, -1) and increasing on (-1, +∞), with a relative minimum at (-1, -1). The second derivative is f''(t) = 36t^2 + 24t, showing concavity changes at (-2/3, 0) and points of inflection at (0,0) and (-2/3, -16/27).

PREREQUISITES
  • Understanding of polynomial functions and their properties
  • Knowledge of first and second derivatives for analyzing function behavior
  • Familiarity with concepts of increasing/decreasing intervals and concavity
  • Ability to identify x-intercepts and y-intercepts from a function
NEXT STEPS
  • Study polynomial function behavior and characteristics
  • Learn how to apply the first and second derivative tests in curve sketching
  • Explore the concept of points of inflection and their significance
  • Practice sketching graphs of various polynomial functions using curve-sketching guides
USEFUL FOR

Students and educators in calculus, mathematicians focusing on polynomial analysis, and anyone interested in mastering curve sketching techniques.

jzq
Messages
54
Reaction score
0
Would someone please help me on this problem? I'm sorry if it is hard to read. I'm new to this forum and haven't had the time to read over the latex system guide. I just need to make sure the information that I got is correct. Thank you.

Sketch the graph of the function, using the curve-sketching guide.

Function: f(t)=3(t)^(4) + 4(t)^(3)

From this function, I derived this information (Please check):
Domain: all real #s
x-int: (0,0)
y-int: (0,0)
Asymptote: none
End Behavior: points up at both ends.
First Derivative: f'(t)=12(t)^(3) + 12(t)^(2)
Decreasing: (-infinity,-1)
Increasing: (-1,+infinity)
Relative Minima: (-1,-1)
This is where I think I messed up!
Second Derivative: f''(t)=36(t)^(2) + 24(t)
Concave Up: (0,+infinity), (-infinity,-2/3)
Concave Down: (-2/3,0)
Points of Inflection: (0,0), (-2/3,-16/27)
 
Last edited:
Physics news on Phys.org
Perfect. Got the same thing.

EDIT: You missed one x-intercept at x = -4/3. Besides that, looks good.
 
Jameson said:
Perfect. Got the same thing.

EDIT: You missed one x-intercept at x = -4/3. Besides that, looks good.
Thanks a lot!
 

Similar threads

  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 3 ·
Replies
3
Views
1K
Replies
3
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 1 ·
Replies
1
Views
1K