Then x+ 1/x = 3.

x？ /x fourth power +X? + 1= 1/X？ +X？ + 1= 1/X？ +X？ +2- 1

=(X+ 1/X)？ - 1=3? - 1=8

2.(X-Y+4XY/X-Y)×(X+Y-4XY/X+Y)

=[(x-y)^2+4xy]/(x-y)×[(x+y)^2-4xy]/(x+y)

=(X+Y)^2/(X-Y)×(X-Y)^2/(X+Y)

=(X+Y)(X-Y)=X^2-Y^2

3. Because the equation (1-M)X=M-2X has only one negative number, we can get (3-M)X=M from (1-m) x = 2x.

So X=M/(3-M)

Because the solution is negative. Then M & gt0.3 m<0 or m

Then M>3 or M

4: A+ 1/A = 6, then (A+ 1/A)? = 36 ,

Answer? + 1/A？ =34

Answer? + 1/A？ -2=32

(A- 1/A)？ =32

A- 1/a = 4 * radical number 2 or -4* radical number 2.

5:K=-6

6: 10