Sum of first n even natural numbers=n(n+1)

1.	Sum of first n even natural numbers=n(n+1)
Answer» AP: ,2,4,6.... To n terma=2,d=2,n=n,sn=n(n+1)Sn=n÷2[2a+(n-1)d]n(n+1)=n÷2[2×2+2n-2]n(2n+2)=n(2n+2)Both sides are same. So, his answer is 0

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