Question

log2(x+1)^2+log4(x+1)=5

log2(x+1)^2+log4(x+1)=5 求x 解题时有一步不懂log4(x+1)=0.5log2(x+1)?

Answer 1

log4(x+1)
=log2(x+1)/log(2)4 (同换以2为底的对数)
=log2(x+1)/2 （log(2)4 =log(2)2²=2log(2)2=2）
=0.5log2(x+1)