n²+n²(n+1)²+(n+1)²2a^4+2b^4+2c^4-2a²b²-2b²c²-2a²c²

n²+n²(n+1)²+(n+1)²
2a^4+2b^4+2c^4-2a²b²-2b²c²-2a²c²

n²+n²(n+1)²+(n+1)²=[n(n+1)]²+2n²+2n+1=[n(n+1)]²+2n(n+1)+1=[n(n+1)+1]²=(n²+n+1)²
2a^4+2b^4+2c^4-2a²b²-2b²c²-2a²c²=(a²-b²)²+(b²-c²)²+(a²-c²)²

n²+n²(n+1)²+(n+1)²=[n(n+1)]²+2n²+2n+1=[n(n+1)]²+2n(n+1)+1=[n(n+1)+1]²=(n²+n+1)²
2a^4+2b^4+2c^4-2a²b²-2b²c²-2a²c
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n²+n²(n+1)²+(n+1)²=[n(n+1)]²+2n²+2n+1=[n(n+1)]²+2n(n+1)+1=[n(n+1)+1]²=(n²+n+1)²
2a^4+2b^4+2c^4-2a²b²-2b²c²-2a²c²=(a²-b²)²+(b²-c²)²+(a²-c²)²

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（1）n^2+n^2*(n+1)^2+(n+1)^2
=n^2+n^2(n+1)*(n+1)+(n+1)^2
=n^2+n^3(n+1)+n^2(n+1)+(n+1)^2
=n^4+n^2(n+1)+n^2(n+1)+(n+1)^2
=(n^2+n+1)^2
2a^4+2b^4+2c^4-2a²b²-2b²c²-2a²c
=(a²-b²)²+(b²-c²)²+(a²-c²)²望采纳o(∩_∩)o...