Question

急，一道关于log的高中数学题！！

已知log12^27=a ,求证:log6^16=(413-a)÷(3+a)
log的底是12

Answer 1

log(12,27)=3log(12,3)=a∴ log(12,3)=a/3
log(6,16)=2log(6,4)=2[log(12,4)]/log(12,6)=2[log(12,12/4)]/[log(12,√36)]
=2[log(12,12)-log(12,3)]/[1/2log(12,12×3)]=[2(1-a/3)]/[1/2(1+a/3)]
=[4(3-a)]/(3+a)

Answer 2

log的底是12吗？