已知2的x次方等于9,2的y次方=8/3,则x+2y=
问题描述:
已知2的x次方等于9,2的y次方=8/3,则x+2y=
答
2∧x=9 x=log?92∧y=8/3y=log?﹙8/3﹚x+2y=log?9+2log?﹙8/3﹚=log?9+log?﹙8/3﹚2=log?[9×﹙8/3﹚2]=log?82=6
已知2的x次方等于9,2的y次方=8/3,则x+2y=
2∧x=9 x=log?92∧y=8/3y=log?﹙8/3﹚x+2y=log?9+2log?﹙8/3﹚=log?9+log?﹙8/3﹚2=log?[9×﹙8/3﹚2]=log?82=6