问题
选择题
a4+4分解因式的结果是( )
A.(a2+2a-2)(a2-2a+2)
B.(a2+2a-2)(a2-2a-2)
C.(a2+2a+2)(a2-2a-2)
D.(a2+2a+2)(a2-2a+2)
答案
a4+4=a4+4+4a2-4a2=(a2+2)2-4a2=(a2-2a+2)(a2+2a+2)
故选D
a4+4分解因式的结果是( )
A.(a2+2a-2)(a2-2a+2)
B.(a2+2a-2)(a2-2a-2)
C.(a2+2a+2)(a2-2a-2)
D.(a2+2a+2)(a2-2a+2)
a4+4=a4+4+4a2-4a2=(a2+2)2-4a2=(a2-2a+2)(a2+2a+2)
故选D