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填空(x-y)(x2+xy+y2)=;(x-y)(x3+x2y+xy2+y3)=根据以上等式进行猜想,当n是偶数时,可得:(x-y)(xn+xn-1y+yn-2y2+…+x2yn-2+xyn-1+yn)=.

题目详情
填空(x-y)(x2+xy+y2)=______;(x-y)(x3+x2y+xy2+y3)=______
根据以上等式进行猜想,当n是偶数时,可得:(x-y)(xn+xn-1y+yn-2y2+…+x2yn-2+xyn-1+yn)=______.
▼优质解答
答案和解析
原式=x3+x2y+xy2-x2y-xy2-y3=x3-y3;故答案为:x3-y3;原式=x4+x3y+x2y2+xy3-x3y-x2y2-xy3-y4=x4-y4;故答案为:x4-y4;原式=xn+1+xny+xyn-2+x2yn-1+xyn-xny-xn-1y2-yn-1y2-…-x2yn-1-xyn-yn+1=xn+1-yn+1,故答案为...