Me Domain

How to find domain of these functions plus finding a linear function which has the given slope and y-intercept
I'm having alot of trouble finding the domain of Questions 1 and 2 and finding the linear function by the slope and y-intercept in question 3, can anyone help and possibly explain in 'easy' terms for me? :) Question 1: f(x) = x^2 - 9 Question 2: f(x) = | 48 - x | Question 3: f(x) = 8 --------- x + 9 Question 4: Find a linear function whose graph has the given slope and y-intercept. Slope 7/3, y-intercept (0,-5) With question 3 would that by 9 if I set x as zero, or am I donig something wrong?

Domain of a function is the range of values the independent variable (here x) can take and range of the function is the range by which the values of the dependent variable [here f(x)] is limited. Q1. f(x) = x^2 - 9 Here x can take all values from minus infinity to plus infinity. Hence the domain of the function is from minus infinity to plus infinity. A squared quantity is always positive. The minimum value of a squared quantity is zero. So the minimum value of f(x) is -9. It can take maximum values up to plus infinity. So the range of the function is from -9 to plus infinity. Q2. f(x) = |48-x| Here x can take all values from minus infinity to plus infinity. Hence the domain of the function is from minus infinity to plus infinity. The modulus of a quantity is its positive value. It can not be negative. So f(x) can take values from zero to plus infinity. So the range of the function is from zero to plus infinity. Q3. f(x) = 8/(x+9) Here x can take any value continuously from minus infinity to plus infinity. Hence the domain of the function is from minus infinity to plus infinity. f(x) also can have any value from minus infinity to plus infinity. So the range of the function is from minus infinity to plus infinity. Q4. The equation of a straight line is given by y=mx+c where m is the slope and c is the y-intercept. Here m = 7/3, c= -5 So the linear relation between y and x is y=(7/3)x -5 or 3y =7x -15.

What is the domain of the function on a numb line?
What is the domain of the function g defined by g(x)=(square root of)2x+18 on a number line?

2x+18>=0 x>=-9

What is the domain and range of reciprocal functions?
In my precalculus book, it says the domain and range of a reciprocal function is (- infinity, 0) U (0, infinity). What does the U symbol stand for?

the U means union or a fancy way of saying and. It includes both sets in their entirety as opposed to an intersection, the upside down U, which means that only the numbers that are included in both sets are the solution. wpf.

How do you set domain restrictions on the ti-83 when your graphing a function?
in precalc we learned that in the y= menu you could restrict the domain to only graph a portion of a function but i've forgotten how. I need to be able to do things like tell it to only grapgh where x<1 and things like that.

Type in the function then directly after the function type inside parenthesis your restrictions. For example Y=2x(x<1) would show the function y=2x only for values of x < 1 The <, >, and other buttons are found by typing [2nd][Math] under the test menu.

What is the difference between a collision and a broadcast domain?
I have read many answers to the quesiton but every answer includes some new term that I am not yet familiar with. Please explain as if it were to a child. (i am the child) also if the collision domain is so problematic why was it made with such high probability of collision?

What the previous respondent left out is that collisions are not a really big problem. Ethernet is set up so that any computer on the segment can transmit at any time, and if it doesn't work (that is, a collision occurs), the sender detects the collision and resends the data a short, random time later. On most normal networks, collisions don't affect network performance too much. If the collision domain gets too big, however, there are more and more collisions and network performance can be seriously slowed down, so networks are generally segmented with bridges or switches. Everything that connects without passing through a router is the broadcast domain -- which means that there can be several segments (collision domains) in the broadcast domain. Broadcasts are generally used for locating a destination, after which the actual transmission only goes to the segment the destination machine is located on.