1] Express as a single logarithm with a coefficient of 1. ![]() SOLUTION Use the laws for working with logarithms. (i) ![]() The logarithm of a product is the equal to the sum of the logarithms. (ii) ![]() The logarithm of a quotient is equal to the difference of the logarithms. (iii) ![]() The logarithm of a power is equal to the power times the logarithm. In this problem all three laws are involved - products, quotients, and powers. Also, we must re-write the square roots as powers (using fractional exponents) in order to be able to use the power rule (iii). ![]() ![]() ![]() ![]() ![]() Now drop the parentheses. ![]() Combine like terms. ![]() ![]() ![]() Since the problem was given in terms of radicals, let's write the final answer likewise in terms of radicals. ![]() 2] Express as a single logarithm with a coefficient of 1. ![]() SOLUTION Here the logarithms are all strung out and the problem is to put them together so that the final answer will look like ![]() Use the three laws (i) - (iii). And, of course, the laws for working with exponents. ![]() ![]() Now combine the logarithms. Differences are replaced by quotients and sums are replaced by products. ![]() ![]() We have done it! We have found that ![]() 3] Expand in terms of simpler logarithmic forms. (a) ![]() SOLUTION Again, re-write the radical in terms of fractional exponents so we can use the power rule (iii). ![]() ![]() ![]() ![]() ![]() Always simply as much as we can. Remember that ![]() So the final answer is ![]() (b) ![]() SOLUTION ![]() This is as far as we can go. There is no law for re-writing the logarithm of a sum! The only laws for working with logarithms are the three laws (i) - (iii) listed above . WARNING! ![]() ![]() (c) ![]() SOLUTION ![]() ![]() ![]() ![]() is the final answer! top Review 2 Problems Only © edmond 2002 |
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