# Thread: Find the open interval...

1. ## Find the open interval...

Find the open interval where the function is changing as requested.
f(x) = - (sqrt(x+3))

2. Originally Posted by ArmiAldi
Find the open interval where the function is changing as requested.
f(x) = - (sqrt(4+3))
A function is always changing, but are you trying to find when it changes from positive to negative values and vice versa?

To do this, find the derivative, set it equal to zero, and solve for x.