Simplify Expression Inside Summation: We first simplify the expression inside the summation. The expression (4!5!×5)21 can be simplified since 5!=5×4! and thus the 4! in the numerator and denominator will cancel out.
Calculate Simplified Expression: After canceling out 4!, we are left with (5×5)(1)/(2) which simplifies to 51/2×51/2=5.
Factor Out Constant: Now we have the simplified series −∑i=1100(−1)i×5. Since 5 is a constant, we can factor it out of the summation.
Evaluate Alternating Series: The series now becomes −5×∑i=1100(−1)i. This is an alternating series where the sign changes with each term.
Final Result: To evaluate the alternating series ∑i=1100(−1)i, we notice that for odd i, (−1)i is −1, and for even i, (−1)i is 1. Since there are an equal number of odd and even terms (50 of each), the series will sum to 0.
Final Result: To evaluate the alternating series ∑i=1100(−1)i, we notice that for odd i, (−1)i is −1, and for even i, (−1)i is 1. Since there are an equal number of odd and even terms (50 of each), the series will sum to 0.Multiplying the result of the series by −5, we get i0.
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