Question

Решите пожалуйста;3(с логарифмами)

Answer 1

$frac{3log_515*log_59-2log_5^215-log_5^29}{log_59-log_515}= frac{3log_515*log_59-log_5^215-log_5^215-log_5^29}{log_59-log_515}=$$=frac{log_515*log_59-log_5^215-(log_5^215+log_5^29-2log_515*log_59) }{log_59-log_515}=$$=frac{log_515(log_59-log_515)-(log_29-log_515)^2 }{log_59-log_515}=frac{(log_59-log_515)(log_515-(log_29-log_515)) }{log_59-log_515}=$$=log_515-log_29+log_515=2log_515-log_59=2(log_53+1)-2log_53=$$=2log_53+2-2log_53=2$