Question

Will someone help with these?

1. What is the domain/range of y= sin x?
2. What is the domain/range of y= cos x?
3. What is the range of y= tan x?

Answer 1

Answer choices on the attachment ^

Answer 2

1. For y=f(x)=sinx, what values of x can we plug into the sin function and get an answer? I think any real number will work, so dom(sinx)=R (the set of real numbers). For the range, we need to know what the output values are. If I still remember my trig correctly, the outputs of the sin function are between one and negative one, inclusive. That means ran(sinx)=[1,1].

2. The cos function is figured out just like the sin. The answers are the same, too.

Answer 3

3. The tan function is a little different. Every time the cos function goes to zero, the tan function gets unbounded (undefined). That means any value of x that is of the form pi/2+2kpi is not in the domain. This gives us dom(tanx)=R\{x| x=pi/2+2kpi, k in Z} and ran(tanx)=R.

Answer 4

Im not understanding the answers, the answers your giving me dont look like the answers i choose from in the attachment above ^

Answer 5

The set of real numbers, R, can also be shown as (-infinity, infinity).
The interval [-1,1] can be shown -1 less than or equal to y less than or equal to 1.
It doesn't seem that they actually asked the question about the domain of tan x.

Answer 6

You have to be a little more flexible about the notations used to describe sets. Most have more than one way to be described; you have to see they are equivalent.

Answer 7

This is what it looks like...

Answer 8

OK, and what don't you understand? I answered the questions there, and one that isn't. What do you need to know?