(1)√24*√27
=2√3*3√3
=6*√3*√3
=6*3
=18
(2)√6 * (-√15)
=-√6*√15
=-√2*√3*√3*√5
=-3√10
(3)√18*√20*√75
=3√2*2√5*5√3
=30√2*√5*√3
=30√30
(4)√3² 乘 4² 乘 5
=3*16*5
=240
二.
(1)√18/√8
=3√2/2√2
=3/2
(2)2倍根號(hào)5分之4倍根號(hào)15
=2√(4/5)*4√15
=2*2√(1/5)*4√15
=16√(1/5)*√5*√3
=16√3
(3)根號(hào)1又3分之2 除 根號(hào)6分之5
=√(5/3)/√(5/6)
=√(5/3)*√(6/5)
=√[(5/3)*(6/5)]
=√2
(4) 3倍根號(hào)xy分之2倍根號(hào)x²y
=2√x^2y/3√xy
=2x√xy/3√xy
=2x/3
三.化簡(jiǎn).
(1)根號(hào)4乘49
=2*7
=14
(2) 根號(hào)300
=10√3
(3)根號(hào)49分之9
=3/7
(4)根號(hào)4c²分之a(chǎn)²b
=a√b/2c