Question 481956
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The 3rd term is given as 15


The 4th term is 15 + d


The 5th term is 15 + 2d


The 6th term is 15 + 3d


But since the 6th term is 2 times the 4th:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ 15\ +\ 3d\ =\ 2(15\ +\ d)]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ d\ =\ 15]


The 3rd term is 15 so the 2nd term is 15 - 15 = 0 and the 1st term is 0 - 15 = -15.



John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
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