Question

Check if my answers are correct? :)

Attached inside is the graph f ' , the derivative of the function f. Determine if the following are increasing or decreasing for each interval.

a) 0 < x < x1
increasing?

b) x1 < 0 < x2
increasing?

c) x2 < x < x3
decreasing?

d) x3 < x < x4
decreasing?

e) x4 < x < x5
increasing?

are these right?? :/

Answer 1

graph!

Answer 2

nope
function increases only if derivative is positive

anywhere on graph where its positive means increasing .... where its negative means decreasing

Answer 3

you would be correct if this was a graph of f
but its the derivative graph

Answer 4

aww darn..

so are they all opposite of what i put then? since i based it off the f(x) graph not the f ' (x) graph?

so

a)decreasing
b) decreasing

c) increasing
d) increasing
e)decreasing

?

Answer 5

no not opposite, look at whether its pos or neg

Answer 6

so a is negative?

Answer 7

on the f(x) graph, so would that mean to get the derivative, it'll have to be positive?

Answer 8

what?
ok for part a ....0<x<x1 the graph of f' is negative right ....this means that f is decreasing in that interval

Answer 9

haha sorry i just realized that my phrasing was odd...

:/

okay so yes :)

so for b, it's positive, so it would be increasing?

Answer 10

and c) positive, so increasing

d) negative so decreasing

and e) negative, so decreasing

do those look right to you now @dumbcow ? :)

Answer 11

yes now you got it

Answer 12

oh yay!! thank you!!:)