SOLUTION: 6 ∑ (2i+1) i=1

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Question 1170529: 6
∑ (2i+1)
i=1
Answer by Edwin McCravy(20059) About Me  (Show Source):
You can put this solution on YOUR website!
First way: substitute the 6 consecutive values of i:

sum%28%282i%2B1%29%2Ci=1%2C6%29%22%22=%22%22%22%22=%22%22%282%2B1%29%2B%284%2B1%29%2B%286%2B1%29%2B%288%2B1%29%2B%2810%2B1%29%2B%2812%2B1%29%22%22=%22%223%2B5%2B7%2B9%2B11%2B13%22%22=%22%2248

Second way: break the sum into basic sum with formulas:

sum%28%282i%2B1%29%2Ci=1%2C6%29%22%22=%22%22sum%28%282i%29%2Ci=1%2C6%29%22%22%2B%22%22sum%28%281%29%2Ci=1%2C6%29%22%22=%22%222%2Asum%28%28i%29%2Ci=1%2C6%29%22%22%2B%22%22sum%28%281%29%2Ci=1%2C6%29%22%22=%22%222%2A%28%286%286%2B1%29%29%2F2%29%22%22%2B%22%226%22%22=%22%222%2A%286%2A7%2F2%29%22%22%2B%22%226%22%22=%22%22cross%282%29%2A%286%2A7%2Fcross%282%29%29%22%22%2B%22%226%22%22=%22%2242%2B6%22%22=%22%2248

Edwin