5x(x2-2x+4)+x2(x+1)的计算结果是( )A.6x3-10x2+20xB.5x3-11x2+20xC.6x3-9x2+20xD.5x3-10x2
题型:单选题难度:简单来源:不详
5x(x2-2x+4)+x2(x+1)的计算结果是( )A.6x3-10x2+20x | B.5x3-11x2+20x | C.6x3-9x2+20x | D.5x3-10x2+20x |
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答案
5x(x2-2x+4)+x2(x+1), =5x3-10x2+20x+x3+x2, =6x3-9x2+20x. 故选C. |
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