2分之1【x-2分之1(x+1)】≤5分之2(x-1)

2分之1【x-2分之1(x+1)】≤5分之2(x-1)

1/2*(x-1/2(x+1))≤2/5(x-1)
1/2*(x-1/2x-1/2)≤2/5(x-1)
1/2*(1/2x-1/2)≤2/5(x-1)
1/4*(x-1)≤2/5(x-1)
-3/20*(x-1)≤0
x-1≥0
x≥1