Question: Math Genesis needed again...?  You will have my many thanks!!!? Find the sum of the first 38 terms of the arithmetic sequence with the first term 2 and thirty -eight term 113.

Answer: The formula for finding the nth term of an arithmetic sequence is\n\nan = a1 + (n - 1)d\n\nYou need the spacing, d:\n\n113 = 2 + (38 - 1)d\n111 = 37d\nd = 3\n\nThe formula for finding the sum of the sequence is\n\nS = n[2a1 + (n - 1)d] / 2\n= 38[2(2) + (38 - 1)3] /2\n= 38(4 + 111)/2\n= 38(115)/2\n= 2185
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