Question

日人

log2のx➕log3のx＝log3の６のxの答えは何？
（日人国大学）

Answer 1

高橋

log2(x)+log3(x) = log3(6) = log3(2×3) = log3(2)+1
log2(x) = log3(x)/log3(2) (底の変換)
log3(x) = tとおくと、t/log3(2)+t = log3(2)+1
t+tlog3(2) = log3(2)(log3(2)+1)
t(1+log3(2)) = log3(2)(1+log3(2))
t = log3(2)
log3(x) = log3(2)
x = 2