A) 5
B) 10
C) 25
D) 32
Correct Answer: C
Solution :
(c): \[lo{{g}_{5}}({{x}^{2}}+x)-lo{{g}_{5}}(x+1)=2\] \[\Rightarrow lo{{g}_{5}}\left( \frac{{{x}^{2}}+x}{x+1} \right)=2\] \[\Rightarrow lo{{g}_{5}}\left[ \frac{x(x+1)}{x+1} \right]=2\] \[\Rightarrow {{\log }_{5}}x=2\Rightarrow x={{5}^{2}}=25\]You need to login to perform this action.
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