# Summations

a) Write an expression in sigma notation as shown for suitable terms n1, n2, and ai, for each of these finite and infinite summations.

b) Use the method of telescopic sums to evaluate these finite sums, using the indicated anti-difference sequences.

c) Which of the following sequences are null? Explain your answer.

See attached file.

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#### Solution Summary

There are three topics in this solution: writing infinite sums in sigma notation, using telescopic sums to evaluate finite sums, and identifying null sequences.

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