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Solve for i in the following equation by means of linear interpolation (1 + i)^10 - 1/ i = 25

User Atyachin
by
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1 Answer

2 votes

Answer:

i = 0.5049202164

Explanation:

the given equation is:


((1+i)^(10-1))/(i) = 25 \\ \\ (1+i)^(10) = 25i + 1 \\ \\ (1+i)^(10)-25i = 1 \\ \\ Taking \ log \ of \ both \ sides ; we \ have: \\ \\ log(1+i)^(10) - log (25 \ i) = log (1) \\ \\ 10 \ log (1+i) - \ log \ (25 \ i) = 0 \ \ \ \ \ (since : log (1) = 0 )) \\ \\ \ log (1+i) = log \ (25 \ i) ^(1/10) \\ \\ log(1+i) = log (1.3627429+0.2158372i) \\ \\ 1+i = 1.3627429+0.2518372 \ i


[ 1 - 0.2518372]i = 1.3627429 -1 \\ \\ 0.784162729 = 0.3627429 \\ \\ i = (0.3627429)/(0.784162729) \\ \\ i = 0.5049202164