Question 1
which of the following is/are true?
A.(2/a-b) (b-a/2) =-1.
B.If x=-1/2 and y=-2 then -x^2 - 4x/y +y^2=2 3/4.
C.√1-x /√x-1 is defined for all x€R,x is not equal to 1.
Question 2
The solution set of -x-√2x^2 +x -5 = 1 is
1.Q
2.{-2}
3.{-2,3}
4.{3}
5.R
first part already answered
I suspect a typo, what with the -x and +x, leaving you with
√2 x^2-5=1
√2 x^2 = 6
x^2 = 6
hmmm. not what you expected. How about
√(2x^2)-5=1
2x^2=36
x^2=18
Hmmm.
Better clean up your notation a bit.