X方-X\2-(X-1)方\3

X方-X\2-(X-1)方\3
X方-X\2-(X-1)方\3<1+(4X-1)(X+2)\6

X方-X\2-(X-1)方\3
两边乘6
3x²-3x-2(x²-2x+1)<6+(4x²+7x-2)
3x²-3x-2x²+4x-2<6+4x²+7x-2
x²+2x+2>0
(x+1)²+1>0
恒成立
所以x属于R

a+b+c=2 (1)
9a+3b+c=2 (2)
25a+5b+c=7 (3)
(2)-(1)
8a+2b=0 (4)
4a+b=0 (5)
(3)-(2)
16a+2b=5 (6)
(6)-(4)
8a=5
a=5/8
b=-4a=-5/2
c=2-a-b=31/8