Use this situation to answer the questions that follow: The surface area of a cube can be found using the following formula: A = 6s2, where A represents the tot

Question

COULD NOT FIGURE IT OUT. Couldn't even understand which was independent and dependent.

 

It asks then,

 

What is the independent variable? What is the dependent variable? Is this continuous or discrete? What is the domain? What is the range?

Answer 1

The domain for s, the independent variable, is all positive numbers. The range for S, the dependent variable, is also all positive numbers.

Independent variable is s because you are free to choose any side length, and with that choice you can compute the cube's area. Variable s is the INPUT, variable A is the OUTPUT.

This function is continuous.

It's rather important to understand (and remember) these fundamental concepts.

As a coping tactic, I suggest that you pay greater attention to your math lecture and when reading the textbook. And as soon as you do not understand something, ask a question in class so that the teacher can do his or her job and you will be recognized as a student interested in learning.

Answer 2

A cube has six faces which are all squares, so the total surface area of a cube is:
     A = 6s²,   where s = length of an edge

When that equation is written with "A" on the left side, it is a function.  The side length, s, is the independent variable and the total surface area, A, is the dependent variable.  [Note that s = √(A/6) is also a function, with A as the independent variable and s as the dependent variable.]

The range of both s and A is all positive values (that is, greater than 0 to infinity).  The given function, A = 6s² is continuous (and, so is the inverse function, s = √(A/6).