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problem with god damn logs (1 Viewer)

ryanox

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if log (base b) a= 3.75 and log (base b) c= 1.25 find the value of:
(a) log (base a) ab
(b) log (base b) (a/c)
(c) log (base b) (ac)2
(d) log (base c) a
 

Riviet

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(a) loga(ab)=logaa + logab
= 1 + logab
= 1 + logbb/logba
= 1 + 1/3.75
= 19/15

(b) logb(a/c)=logba - logbc
=3.75 - 1.25
=2.5

(c) Did you mean logb(ac)2 ?
If so, then
logb(ac)2=2logbac
=2(logba + logbc)
=2(3.75 + 1.25)
=2 x 5
=10

(d) logca=logba/logbc
=3.75/1.25
=3
 

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