6x方-5x-1＞0 4x方+4x-15≤0 5x方-2x+3＞0 9x方+6x+1＞0 3x方-4x+5＜0 6x方+5x＜4 _数学解答

6x方-5x-1＞0 4x方+4x-15≤0 5x方-2x+3＞0 9x方+6x+1＞0 3x方-4x+5＜0 6x方+5x＜4 -x方+5x-5＞1

人气：296 ℃　时间：2020-03-30 04:18:40

解答

1.6x²-5x-1=(x-1)(6x+1)＞0,x＞1或x＜-1/62.4x²+4x-15=（2x-3)(2x+5)≤0,-2/5≤x≤2/33.9x²+6x+1=(3x+1)²＞0,x∈R4.3x²-4x+5＜0,因为a=3＞0,△=-44＜0,所以x∈R5.6x²+5x＜4,6x²+...