化簡'開方'~[help]!!!~~~~

1.
10/√5
=(10/√5)×(√5/√5)
=(10√5)/5
=2√5
2.
(4√3)/√2
=(4√3)/√2×√2/√2
=[(4√3)×√2]/2
=(4√6)/2
=2√6
3.
2/√18
=2/√(3×3×2)
=2/(3√2)
=2/(3√2)×√2/√2
=2√2/[(3√2)(√2)]
=2√2/(3×2)
=2√2//6
=√2/3
4.
(√5-√2)/√10
=(√5-√2)/√10×(√10/√10)
=√10(√5-√2)/10
=[√(10×5)-√(2×10)]/10
=[√(2×5×5)-√(2×2×5)]/10
=(5√2-2√5)/10
=(√2)/2-(√5)/5
5.
[√6+√2]/2√3
=[√6+√2]/2√3×√3/√3
=√3[√6+√2]/[2×3]
=√(3×3×2+√(3×2)/6
=[3√2+√6]/6
=(√2)/2+(√6)/6
6.
(√2+√3-1)/√5
=(√2+√3-1)/√5×√5/√5
=[√(2×5)+√(3×5)-√5]/5
=(√10+√15-√5)/5

WHAT IS THIS???????????????????????????????????????????????????