If 1, log x (base y), log y (base z), -15 log z (base x) are in AP, then a) z^3 = x b) x = y^-1 c) z^-3 = y d) all of these Regards Sreedhar
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Let the common difference be d. Then the progression is 1, d+1, 2d+1, and 3d+1, so Combining the first two gives , and equating exponents gives (3d+1)(2d+1)(d+1)=-15, with the only solution d=-2. - Hollywood
Hello, yshridhar! Lovely work, Hollywood! . . Hollywood had: . Then we have: . . . . . . Answer: .
Thanks alot Hollywood for such a simple solution. I am banging with logarithms formulae for this sum. Regards Sridhar
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