f'(x) < 0 if |x| < 1

And apparently this means f is decreasing on (-1, 1).

I don't understand this. I know f'(x) < 0 means the function is decreasing. But I don't understand the absolute value. It means I can put -1 or 1 inside, but wouldn't it still be 1 = 1 and not 1 < 1? I don't understand.

asked by Kelly
  1. Consider f(x)=x^2 -1

    f(x) <0 if abs(x)<1
    However, f(x) is not decreasing over that entire range (-1 to 1)

    So your meaning of the problem statement is not understood

    posted by bobpursley
  2. Sorry, I don't understand your reply...

    This question has a prime after the f by the way. It's f prime, aka the derivative. That's why the function is decreasing.

    posted by Kelly

Respond to this Question

First Name

Your Response

Similar Questions

  1. spanish

    So i am a little confused about two different words in spanish. Apparently caer means to fall but caerse means to get married. am I correct on this? Why are the verbs the same but when you add the reflexive to it is means a whole
  2. biology

    I understand that a prokaryotic cell has ribosomes smaller than 70s. But what i don't understand is what 70s accutually means. Please could someone explain what 70s means to me? thank you
  3. math{HELP HELP}

    i don't understand these mmath equations. 1) 6y = 24 2)y / 7 = 2 y=_________ On number one i know that if there is a letter next to a number it means multiplication.and i still don't know how to solve it. On number two i don't
  4. math... Ms, Sue can you help?

    Apparently, I got this question wrong on a test and I'd like to know what error I made... can you help? Here's what I did: 2b^2+b=6 b^2+1/2b=3 b^2+1/2b+(1/2)^2=3+(1/2)^2 (b+1/2)^2=3+1/4 b+1/2=+/- <13/4> b=-1/2+/-<13>/2

    I have a bit of information on Negative articles in french and stuff. Like I know there is Ne+ Pas Ne...Plus Ne...Rien Ne...Jamais Ne...Que Ne....Personne Ne Pas means: not, don't etc--a lot for this Ne plus means: not anymore, no
  6. chemistry.

    I attempted to answer some but I just don't know if what I wrote is correct so will you please help me figure out these answers. Predict the effect that the following changes or stresses would have on the given equilibrium, a)
  7. Calculus

    For y=(1/4)x^4-(2/3)x^3+(1/2)x^2-3, find the exact intervals on which the function is a. increasing b. decreasing c. concave up d. concave down Then find any e. local extreme values f. inflection points --- I thought it'd be
  8. I don't understand this chemistry problem?

    The question reads: Place the following elements in order of decreasing atomic size: selenium, chlorine, fluorine, rubidium, calcium, and sulfur. I looked this up on a periodic table and my answer was: Rb, Se, Ca, Cl, F, S. This
  9. English Help

    Type a short character sketch of a fictional Puritan named Justice Johnson based on what you have learned about the Puritans. Make certain that you describe how he dresses, how he lives, what he believes, how he spends his
  10. Logic

    I need help with these advanced excercises in logic. They're really hard, and my teacher said they should take at least a month. Here's just one, if you can show me how I'm sure I'll be able to get the rest of them. There's

More Similar Questions