1.x²-3x-4≥3x-x²+4或x²-3x-4≤-(3x-x²+4)2x²-6x-8≥0x²-3x-4≥0(x-4)(x+1)≥0x≥4或x≤-12.x²-5mx+4m²>0(x-4m)(x-m)>0当m>0时,x>4m或x0当m
