square root of (4-9/2)^2 ......can't we write it as (9/2-4)^2...??
so it dives 1/2=1/2 which is true..
actually...the square root sign that we use means '+ve' square root....i.e. we have to take the +ve value out of it.. u might have notices that graph of y=root (x) lies exactly above x-axis so that all y are +ve being equal to square root of x...
as i mentioned before one of the definitions of square root can be given by "square root of x^2 is |x|"