化简：2a²-［5a-1/2(a-3)+2a²］2a²-［5a-1/2(a-3)+2a²］要每一步的过程

化简：2a²-［5a-1/2(a-3)+2a²］2a²-［5a-1/2(a-3)+2a²］要每一步的过程
化简：2a²-［5a-1/2(a-3)+2a²］
2a²-［5a-1/2(a-3)+2a²］要每一步的过程

化简：2a²-［5a-1/2(a-3)+2a²］2a²-［5a-1/2(a-3)+2a²］要每一步的过程
2a²-［5a-1/2(a-3)+2a²］
=2a²-(5a-1/2a+3/2+2a²)
=2a²-5a+1/2a-3/2-2a²
=-9/2a-3/2

2a²-［5a-1/2(a-3)+2a²］
=2a²-[5a-1/2a+3/2+2a²]
=2a²-4.5a-1.5-2a²
=-4.5a-1.5

2a²-［5a-1/2(a-3)+2a²］
=2a²-(5a-1/2a+3/2+2a²)
=2a²-(2a²+9/2a+3/2)
=2a²-2a²-9/2a-3/2
=-9/2a-3/2

解:2a^2-5a+1/[2(a-3)]-2a^2
-5a[2(a-3)]/[2(a-3)]+1/[2(a-3)]
(10a^2-30a+1)/5a