Question

$log_{5}(25) + ) log_{7}(49) + log(10) - 15 log_{2}(2)$

Answer 1

$log_{5}(25) + log_{7}(49) + lg10 - 15 log_{2}(2)$

$= 2 + 2 + 1 - 15 \times 1 = 5 - 15 = - 10$