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Find the sum of the finite series. \newline i=150(2i1)(2i+1)\sum_{i=1}^{50} (2i-1)(2i+1) \newline______

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Q. Find the sum of the finite series. \newline i=150(2i1)(2i+1)\sum_{i=1}^{50} (2i-1)(2i+1) \newline______
  1. Simplify Expression: We start by simplifying the expression (2i1)(2i+1)(2i-1)(2i+1) using the difference of squares formula, which states that a2b2=(ab)(a+b)a^2 - b^2 = (a - b)(a + b). Here, a=2ia = 2i and b=1b = 1, so the expression simplifies to 4i214i^2 - 1.
  2. Distribute Summation: Next, we distribute the summation from i=1i=1 to 5050 into 4i214i^2 - 1. This separates the series into two parts: i=1504i2\sum_{i=1}^{50}4i^2 and i=1501-\sum_{i=1}^{50}1.
  3. Evaluate First Term: We evaluate the first term i=1504i2\sum_{i=1}^{50}4i^2 using the summation formula for the sum of squares, which is i=1ni2=n(n+1)(2n+1)6\sum_{i=1}^{n}i^2 = \frac{n(n+1)(2n+1)}{6}. Plugging in n=50n = 50, we get:\newlinei=1504i2=4×(50(50+1)(2×50+1)6)\sum_{i=1}^{50}4i^2 = 4 \times \left(\frac{50(50+1)(2\times50+1)}{6}\right)\newline=4×(50×51×1016)= 4 \times \left(\frac{50\times51\times101}{6}\right)\newline=4×2550×1016= 4 \times \frac{2550\times101}{6}\newline=4×2575506= 4 \times \frac{257550}{6}\newline=4×42925= 4 \times 42925\newline=171700= 171700
  4. Evaluate Second Term: We evaluate the second term i=1501\sum_{i=1}^{50}1 which is simply the sum of 11 repeated 5050 times. This is equal to 5050.
  5. Subtract and Find Answer: Finally, we subtract the result of the second term from the first term to get the final answer: 17170050=171650171700 - 50 = 171650.

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