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I'm unsure what this question is asking - can anyone help?

Find the sum of integers above n, up to and including 2n, giving your answer in a fully factorised form.

Reply 1

mqb2766

Original post by beachpanda

I'm unsure what this question is asking - can anyone help?

Find the sum of integers above n, up to and including 2n, giving your answer in a fully factorised form.

You could write it as the
sum from r=1 to 2n of r
And subtract off the
sum from r=1 to n of r

If you're unsure, write down the first few and last few terms in the sum.

Reply 2

beachpanda

Original post by mqb2766

You could write it as the
sum from r=1 to 2n of r
And subtract off the
sum from r=1 to n of r

If you're unsure, write down the first few and last few terms in the sum.