Question

Exprimati in functie de a=log_20 (2) numarul b = log_5 (20)

Answer 1

Răspuns:

$\frac{1}{1-2a}$

Explicație pas cu pas:

$log_{5}20$ = $\frac{log_{20}20 }{log_{20}5 }$ = $\frac{1}{log_{20}(\frac{20}{4} ) }$ = $\frac{1}{log_{20}20 - log_{20}4  }$ = $\frac{1}{1-2log_{20}2 }$ = $\frac{1}{1-2a}$