来自胡家骥的问题
求不等式的正整数解(2X+3)2-(2X+3)(2X-5)》7X+54(2X+3)²-(2X+3)(2X-5)>7X+54
求不等式的正整数解
(2X+3)2-(2X+3)(2X-5)》7X+54
(2X+3)²-(2X+3)(2X-5)>7X+54
1回答
2020-06-28 20:50
求不等式的正整数解(2X+3)2-(2X+3)(2X-5)》7X+54(2X+3)²-(2X+3)(2X-5)>7X+54
求不等式的正整数解
(2X+3)2-(2X+3)(2X-5)》7X+54
(2X+3)²-(2X+3)(2X-5)>7X+54
先化简
4x^2+12x+9-(4x^2-4x-15)>7x+54
12x+4x+24>7x+54
16x-7x>54-24
9x>30
x>10/3
因为是求正整数解,所以不等式的解集是{x|x=n+4,n∈N}