Please help me out, Its drivin gme crazy because I cant answer it. Find the sum of the first 29 terms 4,8,16,32
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Originally Posted by amandaggogo Please help me out, Its drivin gme crazy because I cant answer it. Find the sum of the first 29 terms 4,8,16,32 As $\displaystyle U_{n+1} = 2U_n$ then you have a geometric sequence with $\displaystyle \text{a = 4, n = 29, r = 2}$ The formula for the sum of a geometric sequence is $\displaystyle S_n = \frac{a(r^n-1)}{r-1}$. Sub in your values and solve Spoiler: $\displaystyle S_{29} = \frac{2(2^{29}-1)}{2-1} = 1 073 741 822$
Thank you very much, that makes much more sense now :0)
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