(1)=(2T+1)(2T+1-2T+1)=2(2T+1)
(2)=(X-2Y)^2-1
(3)=4x^2+12xy+9y^2-4x^2+y^2-10y^2-5xy
=7xy
=7·(1/3)·(-1/2)
=-7/6
(4)=x^2-4x+4+3x^2-3-2x^2-2x+x+1
=2x^2-5x+2
=2·(-1/2)^2-5(-1/2)+2
=5
(5)=(1-3a)(1-3a-2)
=(3a-1)(3a+1)
(6)=x^2-2x+1-2x+2-x^2
=-4x+3
(7)=2x^2-3x+1-x^2-2x-1+1
=x^2-5x+1
=14+1
=15
不给分,还这么多题,算了. 只能帮你顶一个了
1, =(2T+1)(2T+1-2T+1)=2(2T+1)
2, =(X-2Y)2-1..................................!
确定初一的吗?好多。不想做