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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 111

Perform the indicated operations. Assume all variables represent positive real numbers. 81x6y3416x10y34\(\sqrt\)[4]{81x^6y^3} - \(\sqrt\)[4]{16x^{10}y^3}

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Rewrite each term using fractional exponents to express the fourth roots: \(\sqrt[4]{81x^{6}y^{3}} = (81x^{6}y^{3})^{\frac{1}{4}}\) and \(\sqrt[4]{16x^{10}y^{3}} = (16x^{10}y^{3})^{\frac{1}{4}}\).
Apply the exponent to each factor inside the parentheses separately using the property \((abc)^m = a^m b^m c^m\): \((81)^{\frac{1}{4}} (x^{6})^{\frac{1}{4}} (y^{3})^{\frac{1}{4}}\) and \((16)^{\frac{1}{4}} (x^{10})^{\frac{1}{4}} (y^{3})^{\frac{1}{4}}\).
Simplify the numerical parts by finding the fourth root of 81 and 16: \$81 = 3^4\(, so \((81)^{\frac{1}{4}} = 3\), and \)16 = 2^4$, so \((16)^{\frac{1}{4}} = 2\).
Simplify the variable parts by multiplying the exponents: \((x^{6})^{\frac{1}{4}} = x^{\frac{6}{4}} = x^{\frac{3}{2}}\), \((x^{10})^{\frac{1}{4}} = x^{\frac{10}{4}} = x^{\frac{5}{2}}\), and \((y^{3})^{\frac{1}{4}} = y^{\frac{3}{4}}\) for both terms.
Rewrite the expression with the simplified parts and then perform the subtraction: \(3 x^{\frac{3}{2}} y^{\frac{3}{4}} - 2 x^{\frac{5}{2}} y^{\frac{3}{4}}\). From here, factor out the common terms if possible to simplify further.

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Key Concepts

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