Mathematics 74 Online
OpenStudy (anonymous):

f(x) = 7 x^2 - 4 x. Find all extreme values (if any) of f and determine the values of x at which these values occur.

OpenStudy (anonymous):

1) Find the derivative $f(x) = 7x ^{2}-4x$ $f'(x) = 14x - 4$ 2) Set the derivative = 0 to find the critical points $14x-4 = 0$ $x = 2/7$ 3) Set up your intervals to determine increasing/decreasing $(-\infty, 2/7) and (2/7, \infty)$ 3a) Find a test point in each interval and substitute into your first derivative to determine if increasing or decreasing. If you get from increasing to decreasing, you have a max. If you get from decreasing to increasing, you have a min. In the first interval, you get a negative (which means the graph is decreasing from -infinity to 2/7). For the second interval, you get a positive (which means the graph is increasing from 2/7 to infinity). Therefore, this means you have a minimum at x = 2/7. If you'd like to know the y-coordinate, simply plug in 2/7 in for x into your original function. Hope this helps! Good luck!

Latest Questions
lovelygirl13: i made a collage of ALL the zodiac signs (this took a while lol)
12 minutes ago 4 Replies 0 Medals
45 minutes ago 0 Replies 0 Medals
JustKOI: a poem just becauuuse...
3 hours ago 5 Replies 10 Medals
madz2345: random stuff from my sketchbook. rate them :0
19 minutes ago 35 Replies 11 Medals
Fredyy: Do you all im doing better!!!pls sub it helps alot!!! thx
1 hour ago 16 Replies 6 Medals
Tyrun: What y'all think of these lyrics. its sad rap
3 hours ago 10 Replies 2 Medals
lovelygirl13: i made a rick and morty collage
1 hour ago 24 Replies 9 Medals
DatBoiAYD: art
16 hours ago 14 Replies 6 Medals