题目内容
A. x2+4
B. x2+2x+4
C. x2-x+
D.x2-4y
A. -x4-y4
B. -4m2+n2
C.-x4
D.(a+b)2-81
A.(-1+0.4x)2
B.(0.4x+1)(0.4x-1)
C.(0.16x+1)(0.16x-1)
D.不能分解