Practice | Hashtable

Home > Practice > Arithmetic Aptitude > Logarithms > Miscellaneous

1. $If log \frac{a}{b} + log \frac{b}{a} = log (a + b),$ then:

A. a + b = 1

B. a - b = 1

C. a = b

D. a² - b² = 1

Solution:

\begin{aligned} \log \frac{a}{b} + \log \frac{b}{a} = \log (a + b) \\ \Rightarrow \log (a + b) = \log (\frac{a}{b} \times \frac{b}{a}) = \log 1 \\ S o, a + b = 1 \end{aligned}

You must login to add comments. Login now.