中二畢氏定理!急!20點

1)Since 6^2 < 45 < 7^26 and 7 are two consecutive numbers between √45.simplify the following
1)18√25/25= 18(5) / 25= 18/5
2) 2√3/5 +3√3 -√(27/4)= 2√3/5 + 3√3 - 3√3/4= 24√3/60 + 180√3/60 - 45√3/60= 159√3/60= 53√3/20Rationalize the denominators
√(27/11)= √ [ (27*11) / (11*11) ]= √(3 * 11 * 9) / 11= 3√33 / 11


2010-08-20 15:39:29 補充：
Corrections :

2) 2√3/5 +3√3 -√(27/4)

= 2√3/5 + 3√3 - 3√3/2

= 12√3/30 + 90√3/30 - 45√3/30

= 57√3 / 30

= 19 √3 / 10

2010-08-20 15:39:48 補充：
Corrections :

2) 2√3/5 +3√3 -√(27/4)

= 2√3/5 + 3√3 - 3√3/2

= 12√3/30 + 90√3/30 - 45√3/30

= 57√3 / 30

= 19 √3 / 10