Question 469492
(a) {{{log (8.4,122)}}}
Use formula {{{log(b,a)=log(c,a)/log(c,b)}}}
The same formula  in terms of natural logarithms {{{log(b,a)=ln(a)/ln(b)}}}
{{{log (8.4,122)=ln122/ln8.4}}}
(b) {{{log (8.4,122)=ln122/ln8.4=4.8040/2.1282=2.2573}}}
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