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Ch. R - Review of Basic Concepts
Lial - College Algebra 13th Edition
Lial13th EditionCollege AlgebraISBN: 9780136881063Not the one you use?Change textbook
Chapter 1, Problem 78

Find each product. Assume all variables represent positive real numbers. (p1/2-p-1/2)(p1/2+p-1/2)

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1
Recognize that the expression \((p^{1/2} - p^{-1/2})(p^{1/2} + p^{-1/2})\) is in the form of a difference of squares: \((a - b)(a + b) = a^2 - b^2\). Here, \(a = p^{1/2}\) and \(b = p^{-1/2}\).
Apply the difference of squares formula to rewrite the product as \( (p^{1/2})^2 - (p^{-1/2})^2 \).
Simplify each term by using the property of exponents \((p^m)^n = p^{mn}\). So, \((p^{1/2})^2 = p^{(1/2) \times 2} = p^1 = p\) and \((p^{-1/2})^2 = p^{(-1/2) \times 2} = p^{-1}\).
Rewrite the expression as \(p - p^{-1}\).
Since \(p^{-1} = \frac{1}{p}\), the expression can also be written as \(p - \frac{1}{p}\), which is the simplified product.

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Key Concepts

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

Properties of Exponents

Understanding how to manipulate exponents is essential, including rules like multiplying powers with the same base by adding exponents and interpreting negative and fractional exponents. For example, p^(1/2) represents the square root of p, and p^(-1/2) is the reciprocal of the square root of p.
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