回答：
#sqrt75 + 2sqrt12-sqrt27 = 6sqrt3#
説明：
#sqrt75 + 2sqrt12-sqrt27#
= #sqrt（3×5×5）+ 2sqrt（2×2×3）-sqrt（3×3×3）#
= #sqrt（3×ul（5×5））+ 2sqrt（ul（2×2）×3）-sqrt（3×ul（3×3））#
= #5sqrt3 + 2×2sqrt3-3sqrt3#
= #5sqrt3 + 4sqrt3-3sqrt3#
= #（5 + 4-3）sqrt3#
= #6sqrt3#
