4a2/3次方×b-1/3次方除以(-3/2a-1/3×b-1/3)
=4a2/3次方×b-1/3次方乘以(-2/3a^1/3×b^1/3)
=8/3a^(2/3+1/3)b^(-1/3+1/3)
=8a/3