x1+x2=-b/a=m
(x1+x2)²=b²/a²=m²
x2²+x2²+2x1x2=n+2c/a=m²
an-2c=am²
an=am²+2c
-b=am
bm=-am²
1/2an+1/2bm+c=1/2(am²+2c)-1/2am²+c
=c+c=2c
-------------------------
这题有问题吧
x²+b/ax+c/a=0
x²-mx+(m²-n)/2=0
Δ=m²-2(m²-n)>=0
-m²>=2n
0我今天写出来了，应该是c-c=0所以结果等于0，你再看看。很感谢哦x1+x2=-b/a=m(x1+x2)²=b²/a²=m²x2²+x2²+2x1x2=n+2c/a=m²an+2c=am²an=am²-2c-b=ambm=-am²1/2an+1/2bm+c=1/2(am²-2c)-1/2am²+c=c-c=0OK了和我写的一样，呵呵