Question

If $lo{g}_{30}3=c,lo{g}_{30}5$ then the value of $lo{g}_{30}8$

• A. 2(1-c-d)
  
• B. 3(1+c+d)
  
• C. 3(1+c-d)
  
• D. 3(1-c-d)

Answer 1

The correct option is D

3(1-c-d)

$lo{g}_{30}8=3lo{g}_{30}2=3lo{g}_{30}\left(30/15\right)=3(lo{g}_{30}30-lo{g}_{30}3-lo{g}_{30}5=3(1-c-d)$