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Ch. 4 - Inverse, Exponential, and Logarithmic Functions
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 5, Problem 29

Solve each equation. In Exercises 11–34, give irrational solutions as decimals correct to the nearest thousandth. In Exercises 35-40, give solutions in exact form. 3(2)x-2 + 1 = 100

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1
Start by isolating the exponential expression on one side of the equation. Subtract 1 from both sides to get: \$3(2)^{x-2} = 100 - 1$.
Simplify the right side: \$3(2)^{x-2} = 99$.
Divide both sides by 3 to isolate the exponential term: \((2)^{x-2} = \frac{99}{3}\).
Simplify the fraction: \((2)^{x-2} = 33\).
To solve for \(x\), take the logarithm base 2 of both sides: \(x - 2 = \log_2(33)\). Then, solve for \(x\) by adding 2 to both sides: \(x = 2 + \log_2(33)\).

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Exponential Equations

Exponential equations involve variables in the exponent, such as 2^(x-2). Solving these requires isolating the exponential expression and often applying logarithms to find the variable's value.
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Logarithms and Their Properties

Logarithms are the inverse operations of exponentials and are used to solve equations where the variable is an exponent. Understanding properties like log(a^b) = b log(a) helps in simplifying and solving these equations.
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Rounding and Decimal Approximations

When solutions are irrational, they are often expressed as decimal approximations rounded to a specified place, such as the nearest thousandth. This involves using a calculator and understanding rounding rules to present the answer correctly.
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