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Ch. 4 - Exponential and Logarithmic Functions
Blitzer - College Algebra 8th Edition
Blitzer8th EditionCollege AlgebraISBN: 9780136970514Non è quello che usi tu?Cambia libro di testo
Capitolo 5, Problema 13

Solve each exponential equation in Exercises 1–22 by expressing each side as a power of the same base and then equating exponents. 31-x=1/27

Guida verificata passo dopo passo
1
Recognize that the equation is \(3^{1-x} = \frac{1}{27}\). The goal is to express both sides with the same base.
Recall that \(27\) can be written as a power of \(3\) because \(27 = 3^3\). Therefore, rewrite the right side as \(\frac{1}{3^3}\).
Use the property of exponents that \(\frac{1}{a^n} = a^{-n}\) to rewrite \(\frac{1}{3^3}\) as \(3^{-3}\).
Now the equation is \(3^{1-x} = 3^{-3}\). Since the bases are the same and the function is one-to-one, set the exponents equal: \(1 - x = -3\).
Solve the equation \(1 - x = -3\) for \(x\) by isolating \(x\) on one side.

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