运用完全平方公式计算,(3+x)^2= (y-7)^2= (7-y)^2= (-2x-3y)^2= (3-3分之1t)^2= (2分之1m-5分之1n )^2=(r-h)^2(4x+3y)^2(-a-b)^2(2分之1m-2)^2(4分之1x-3分之2y)^2(2x-2.5)^2
问题描述:
运用完全平方公式计算,(3+x)^2= (y-7)^2= (7-y)^2= (-2x-3y)^2= (3-3分之1t)^2= (2分之1m-5分之1n )^2=
(r-h)^2
(4x+3y)^2
(-a-b)^2
(2分之1m-2)^2
(4分之1x-3分之2y)^2
(2x-2.5)^2
答
(3+x)^2=9+6x+x^2(y-7)^2=y^2-14y+49(7-y)^2=49-14y+y^2(-2x-3y)^2=4x^2+12xy+9y^2(3-3分之1t)^2=9-2t+1/9t^2(2分之1m-5分之1n )^2=1/4m^2-1/5mn+1/25n^2(r-h)^2=r^2-2rh+h^2(4x+3y)^2=16x^2+24xy+9y^2(-a-b)^2=a^...