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f(13)=26000(0.90)^13
We move all terms to the left:
f(13)-(26000(0.90)^13)=0
We add all the numbers together, and all the variables
f13-(26000(0.9)^13)=0
We add all the numbers together, and all the variables
f^13-6608.8511536554=0
We do not support efpression: f^13
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