Question

please solve that question

Answer 1

x = 2 + √3

1/x =       2 - √3             = 2 - √3

         (2 + √3) (2-√3)

x + 1/x = 2 + √3 + 2 - √3 = 4

12th can't answer. I put even in computer calculator, but didn't work

13.

(-x/2 + y + 1/4)²

 x²    + y² +     1     -   xy  -     x     +    y

 4                  16                     4           2