|x + 1|  we set x + 1 = 0 and get x = -1, so
|x + 1| means x + 1 if x > -1 and -x-1 if x < -1  
-------------------------
|2x - 1|  we set 2x - 1 = 0 and get x =  , so
|2x - 1| means 2x - 1 if x >
, so
|2x - 1| means 2x - 1 if x >  and -2x +1 if x <
 and -2x +1 if x <  ------------------------------
|x² + 1| means x² + 1 because x² + 1 is always positive. 
------------------------------
|1 - 2x²|  We set 1 - 2x² = 0 and get 
                    -2x² = -1
                      x² =
 
------------------------------
|x² + 1| means x² + 1 because x² + 1 is always positive. 
------------------------------
|1 - 2x²|  We set 1 - 2x² = 0 and get 
                    -2x² = -1
                      x² =  x =
                       x =  , so
|1 - 2x²| means 1-2x² if
 , so
|1 - 2x²| means 1-2x² if  < x <
 < x < and -1 + 2x² otherwise.
If this isn't what you mean, you can express what you mean
in the thank you note and I'll email you.
Edwin
and -1 + 2x² otherwise.
If this isn't what you mean, you can express what you mean
in the thank you note and I'll email you.
Edwin