SOLUTION: how do i rewrite these expressions using absolute value symbol: lx+1l l2x-1l lx^2 +1l l1-2x^2l

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Question 703327: how do i rewrite these expressions using absolute value symbol:
lx+1l
l2x-1l
lx^2 +1l
l1-2x^2l

Answer by AnlytcPhil(1807) About Me  (Show Source):
You can put this solution on YOUR website!
|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  

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|2x - 1|  we set 2x - 1 = 0 and get x = 1%2F2, so

|2x - 1| means 2x - 1 if x > 1%2F2 and -2x +1 if x < 1%2F2 

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|x² + 1| means x² + 1 because x² + 1 is always positive. 

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|1 - 2x²|  We set 1 - 2x² = 0 and get 
                    -2x² = -1
                      x² = 1%2F2
                       x = %22%22+%2B-+sqrt%282%29%2F2 , so

|1 - 2x²| means 1-2x² if %22%22+-+sqrt%282%29%2F2 < x <%22%22+%2B+sqrt%282%29%2F2

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