What is the domain of the following function?

f(x) = √ -x + 2 - 1

You will have to use brackets to show where the square root ends

I suspect it is f(x) = √(-x+2) - 1 , or else why not combine the +2-1 ?

then the number under the square root must not be negative, that is ...
-x + 2 ≥ 0
-x ≥ -2
x ≤ 2

depends. How much of all that is under the radical sign?

Once you specify that, just remember that the domain of √u is u>=0.

To determine the domain of a function, we need to identify any values of x that would make the function undefined.

In this case, we have the function:

f(x) = √(-x + 2) - 1

The square root function (√) is defined for non-negative real numbers. Therefore, the expression inside the square root, -x + 2, must be greater than or equal to 0 for the function to have a real value.

To solve this inequality, we can isolate x:

-x + 2 ≥ 0

Adding x to both sides:

2 ≥ x

Rearranging the inequality:

x ≤ 2

So the domain of the function is all real numbers less than or equal to 2, or in interval notation, (-∞, 2].