May 8

Week 11–Math 10

This week we learnt the chapter 7 — Relations and Functions.  From this week’s classes, I got some hints.

• The variable has coefficient is the independent variable, so another variable is the dependent variable.
• Independent variable, input, and domain these words are the same meaning; Dependent, output, and range mean the same.
• The different ways a relation may be represented are: equation, the graph, the words, table of values, set of ordered pairs, mapping, function notation.
• Every time you need at least three points to graph.
• The discrete variables— data that is counted–there are only some points on the graph–can not interpolate as points in between– no meaning
• The continuous variable— data that is measured–there is a line on the graph, the points are connectedmeaning
• The equation has degree onelinear; The equation has more that two degrees or equal twono linear
• X-intercept => y=0, (x,0)
• Y-intercept=>x=0, (0, y)
• Every time you do the question like this “Determine the x- and y- intercepts of each equation.” at the end, you need answer as ordered pairs. If you meet a situation like this “-y^2=81” you can not figure it, you just write down no y-intercept.
• When you do the question like “State the domain and range for each relation.” if you see there is only dots on the graph, you just list their domains, remember “no repeat”; If the line is continuous, no end, you just write down — D={xER} or R={yER}; Every time the line is continuous, you need have this at the end, {xER}{yER}.
• Functions — input only has one output. But output can have two inputs.