6x²+6<0x²≥0,6>0x²+6>0 при любом хОтвет x∈∅7(2x²-x)/x≤0x(2x-1)/x≤02x-1≤0,x≠02x≤1x≤0,5x∈(-∞;0) U (0;0,5]8(x²-x)/x≤0x(x-1)/x≤0x-1≤0,x≠0x≠1x∈(-∞;0) U (0;1]9x²(x-1)(x+2)²(3+x)≤0x=0 x=1 x=-2 x=-3 + _ _ _ +-----------[-3]-----------[-2]-------------[0]------------[1]-----------------------x∈[-3;1]