Results 1 to 2 of 2

Math Help - Domain/Range and Absolute values

  1. #1
    Junior Member
    Joined
    Jun 2007
    Posts
    52

    Domain/Range and Absolute values

    1.) state the domain and range of each relation, then determine if the relation is a function.

    a) y= -2(x+1)^2-3

    b) y=1/x+3

    c) 2sinx


    2.) Evaluate

    a) l-22l / l-11l + -16/ l-4l
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    9
    Quote Originally Posted by Skoz View Post
    1.) state the domain and range of each relation, then determine if the relation is a function.

    a) y= -2(x+1)^2-3
    The domain are all real x.
    Remember that (x+1)^2\geq 0 \implies -2(x+1)^2 \leq 0 \implies -2(x+1)^2 \leq -3 so the range is y\leq -3.

    b) y=1/x+3
    The domain are all x\not = 0.
    As for the range we have y>3 \text{ or }y<-3.
    To see this picture the hyperbola y=x and shift it up 3 units.

    c) 2sinx
    The domain are all real x and remember that -1\leq \sin x\leq 1 \implies -2\leq 2\sin x\leq 2.
    Thus, range is |y|\leq 2.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: June 1st 2011, 01:47 AM
  2. Replies: 8
    Last Post: May 23rd 2010, 10:59 PM
  3. domain and range of a absolute value function
    Posted in the Algebra Forum
    Replies: 2
    Last Post: March 16th 2010, 07:39 AM
  4. Replies: 2
    Last Post: November 8th 2009, 01:52 PM
  5. Replies: 6
    Last Post: September 16th 2009, 06:25 AM

Search Tags


/mathhelpforum @mathhelpforum