Solve for n
n=-1
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2\times 11^{-n+1}=242
Use the rules of exponents and logarithms to solve the equation.
11^{-n+1}=121
Divide both sides by 2.
\log(11^{-n+1})=\log(121)
Take the logarithm of both sides of the equation.
\left(-n+1\right)\log(11)=\log(121)
The logarithm of a number raised to a power is the power times the logarithm of the number.
-n+1=\frac{\log(121)}{\log(11)}
Divide both sides by \log(11).
-n+1=\log_{11}\left(121\right)
By the change-of-base formula \frac{\log(a)}{\log(b)}=\log_{b}\left(a\right).
-n=2-1
Subtract 1 from both sides of the equation.
n=\frac{1}{-1}
Divide both sides by -1.
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