3.17: Single lg and quadratic in log_c 3

0606/13/M/J/23 — Question 3 · 8 marks · Log laws, Change of base, Equations

(a)
Write 3+2lga12lg(4b2)3 + 2\lg a - \dfrac{1}{2}\lg(4b^{2}), where aa and bb are both positive, as a single logarithm to base 1010. Give your answer in its simplest form.
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(b)
Given that 2logc3=7+4log3c2\log_{c} 3 = 7 + 4\log_{3} c, find the possible values of the positive constant cc, giving your answers in exact form.
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