(-a+1)(a+1)(a2+1)等于( )A.a4-1B.a4+1C.a4+2a2+1D.1-a4
题型:单选题难度:简单来源:不详
(-a+1)(a+1)(a2+1)等于( )A.a4-1 | B.a4+1 | C.a4+2a2+1 | D.1-a4 |
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答案
(-a+1)(a+1)(a2+1), =(1-a2)(a2+1), =1-a4, 故选D. |
举一反三
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