Inequalities/writing set in interval notation
So far I've gathered that the critical numbers are x = 1 and x= -2. I graphed them on the number line. I plugged in test values for each of them.
When I do that, for every test value I've plugged in they've been .
Now I don't know what that means. Does that mean that since every test proved to be a positive, it'll be the whole thing?
The test intervals were .
I'm also confused on this problem:
I already know what it turns into.
That wasn't the hard part. The hard part is figuring out the critical numbers for this.
1 -x+x -x^2
is supposed to be a critical number, but I don't know how you get that.