Вычислитеlog5 49/ log5 2-1/log7 2-log2 14

Question

Вычислите
log5 49/ log5 2-1/log7 2-log2 14

Answer 1

Loga b= log c b/log c a
log5 49/log5 2=2*log5 7 /log5 2=2 log2 7
log2 7=1/log7 2
log2 14= log2 2*7=log2 2 + log2 7
2 log2 7 - log2 7 - 1 - log2 7=-1
равно -1