A:an, the
B:a, the
C:a, /
D:/, the
48-24=____
99-66=____
46-24=____
64-23=____
A long time ago, there is a craftsman.
____改为____
设a,b,c是某三角形的三边长,证明a2(b+c﹣a)+b2(c+a﹣b)+c2(a+b﹣c)≤3abc.