Thread: Domain

find the domain of -4sin(3x)

sin(x) is defined for all real numbers, so are sin(3x) and -4sin(3x)

Originally Posted by papex

sin(x) is defined for all real numbers, so are sin(3x) and -4sinsin(3x)

I want to find the domain of -4 sin (3x).

Hello winsome

Do you understand what is meant by the word domain of a function? It is the set of valid inputs to that function. For example, the domain of is the set of non-negative numbers.

Now, as papex has said, , and therefore and , are defined for all values of . In other words, the domain of these functions is the set of all real numbers.

There are various ways of writing this set. One is to use the symbol . Another is to use interval notation: .

Grandad