(1)由(2½+3½)²
=(2½)²+2×2½×3½+(3½)²
=2+2√6+3
=5+2√6.
(2)由³√72÷√3
=³√(2³×3²)÷√3
=2×(81/27)^(1/6)
=2×3^1/6.(2倍的3的开6次方.