problem:
Quantity A Quantity B
x2 + 1 2x-1
A. Quantity A is greater
B. Quantity b is greater
c. Two quantities are equal
d. Relationship can not be determined, from the information given
Lets set them equal:
$x^2+1=2x-1$
$(x-1)^2=-1$
There are no real values for $x $ that will make that equality true. So, plug in a number (say 0). We find that Quantity A is greater. Since both expressions are continuous, this relationship can only change if at some point the two quantities are equal. Therefore, the answrr is A