Pre Cal/Logarithism

given that f(x)=11^x, find x when f(x)=7
a) x=Ln(7/11)
b) x=Ln7/Ln11
c) x= 7/11
d) x= ll sub 7 11

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asked by Angela
  1. so you solving:
    11^x = 7
    take ln of both sides

    ln(11^x) = ln7
    x(ln11) = ln7
    x = ln7/ln11

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    posted by Reiny

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