What is the approximate value of c which minimises |a_100|? Where a_n = (8+c)*2^n - (7+c)*3^n Thank you for helping out!
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Originally Posted by DaRush19 What is the approximate value of c which minimises |a_100|? Where a_n = (8+c)*2^n - (7+c)*3^n Thank you for helping out! $\displaystyle |a_{100}|$ is minimised when $\displaystyle (8+c)\times 2^n=(7+c) \times 3^c$ when it is zero. Which is equivalent to: $\displaystyle (8+c)=(7+c)(3/2)^{100}$ now rearrange: $\displaystyle c=\frac{8-7(3/2)^{100}}{(3/2)^{100}-1}\approx -7 $ CB
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