Bonjour,
[tex] 8877.4=34530*\dfrac{0.09}{1-(\dfrac{1}{1.09} )^n}\\\\
1-(\dfrac{1}{1.09} )^n=\dfrac{34530*0.09}{8877.4} \\\\
(\dfrac{1}{1.09} )^n=\dfrac{8877.4-34530*0.09}{8877.4}\\\\
n=\dfrac{ln(8877.4)-ln(8877.4-34530*0.09)}{ln(1.09)}\\\\
n\approx{5,0000017873895653125909642807226...}
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