8的x次方=3,8的y次方=2,则8的x+2y次方=_____.

问题描述:

8的x次方=3,8的y次方=2,则8的x+2y次方=_____.

8^(2y)=2x2=4
∴8^(x+2y)=3x4=12

=8的x次方×8的2y次方
=8的x次方×(8的y次方)²
=3×2²
=12

原式=8的x次方×8的2y次方
=8的x次方×(8的y次方)²
=3×2²
=12