Functions

=FUNCTIONS= How can you tell if a relation is a function?

a) Given ordered pairs? If each X value only has one Y number value. (ex. [3,2][2,3] each X only has one Y) b) Given a graph? One could draw a vertical line throught the graph and if the the line hits more then one point at a time then you would know its not a function. by using a vertical line test. you draw a vertical line through the graph and if it hits two points it is not a function. __How do you find DOMAIN and RANGE in the following situations?__

a) Given ordered pairs? by looking at the set and knowing that the first number is the x or the range and baiscally just write them in order least to greatest so the same for the second value AKA the y and the domain.(brooke)

b) On a graph? Deb: You just look at the lowest and highest points on both axes (X and Y). The domain is found on the X axis and Range is found on the Y axis. You can tell if its a function on a graph by being able to draw a vertical line anywhere and only hitting one point at a time.

~ (Taylor) By finding the domain (x-axis) and range (y axis) you see the highst point the line reaches on the domain or range and the lowest. And to tell if the graph is a function you can do the verticle test. By drawing a a verticle line through the graph and see how many lines it goes through.

c) How do you find Domain in an equation? If you have an equation then you set it equal to zero and then it cannot be that number. An example is y= x-3, so x cannot equal 3. (anne) __Function Notation__

How do you find f(a number) such as f(2).... - F(a number) is the value of x in an equation. Example f(x)= x +5 2 +5 =7

a) On a graph? you plug 2 in for the x axis and find where on the y axis the point meets, for instince if the point was (2,3) since you are given f(2), f=3-kp b) In an equation?

c)Given ordered pairs?

What is the difference between finding f(2) in an equation or finding x when f(x) = 2? Deb: f(2) means that 2 is being plugged into the equation in place of X. But f(x) means that X=2 and no work is needed. [not sure about this but I tried]

__What are some tips about graphs of functions/writing stories from the graph?__

__Slope__

How do you find the equation of a line? What do you need to know to find the equation? y= m(x) + B, You need to know M which is the slope, B which is the y intercept and x and y which are the points on the line.-kp Parallel lines - what kind of slope? Give an example. to make parallel lines you can use the same slope. ex. y=2/3x+4 is the first line the parallel line equation is going to look like this, y=2/3x-6.

Perpendicular lines - what kind of slope? Give an example. Perpendicular lines are the oppisit reciprical of the first the slope!