(2x+1)(x-3)>3(x2+2)解不等式

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(2x+1)(x-3)>3(x2+2)解不等式
(2x+1)(x-3)>3(x2+2)解不等式

(2x+1)(x-3)>3(x2+2)解不等式
(2x+1)(x-3)>3(x2+2)
2x²-5x-3>3x²+6
-x²-5x-9>0
x²+5x+9

2X^2-5X>3X^2+6
-X^2-5X-6>0
X^2+5X+6<0
(X+2)(X+3)<0,
由X+2与X+3异号得
-3

(2x+1)(x-3)>3(x2+2)
2x^2-5x-3>3x^2+6
0>x^2+5x+9
x^2+5x+9<0
(x+2.5)^2+2.75<0
因 为(x+2.5)^2≥0
所以原不等式无解
即解集为空集