计算：(1)5√12乘以3√18 (2)√54乘以(-√48) (3)√1.2乘以√3.6 (4)√18除以(√8乘以√

(5√12)*(3√18)
=5*3*√(12*18)
=15√216
=15√(6^2*6)
=15*6√6
=90√6
(√54)*(-√48)
=-√(3^2*6*4^2*3)
=-3*4√18
=-12√(3^2*2)
=-36√2
(√1.2)*(√3.6)
=√(1.2^2*3)
=1.2√3
√18/[(√8)*(√27)]
=√[18/(8/27)]
=√(1/12)
=√(3/36)
=(√3)/6