Solving the system of inequalities 2 (x-1) ≤ 4-x, 3 (x + 1)

Solving the system of inequalities 2 (x-1) ≤ 4-x, 3 (x + 1)

2（x-1)≤4-x,
2x-2

3 (X-Y) & # 178; - 7 (X-Y) + 8 (X-Y) & # 178; + 6 (X-Y) for detailed process
（2） 5xy-4x²y-8xy²+3xy-xy²+4x²y

The original formula = (3 + 8) (X-Y) & #178; + (- 7 + 6) (X-Y)
=11(x-y)²-(x-y)
The original formula = (5 + 3) XY + (- 4 + 4) x & # 178; y + (- 8-1) XY & # 178;
=8xy-9xy²

If x + 1 / x = 7, then x & # 178; + 1 / X & # 178=

The solution is x ^ 2 + 1 / x ^ 2
=x^2+1/x^2+2-2
=(x+1/x)^2-2
=7^2-2
=47.

If (x + 1 / x) ² = 8, then (x-1 / x) ² =?

If (x + 1 / x) ² = 8, then
The value of (x-1 / x) &# is
=(x+1/x)²-4
=8-4
=4;