Question

Calculati dupa ce ati scos factorii de sub radical :

1. √1805 - (√1620-√845) - √720
2. √160 - (√810 - √9610 + √6760)
3. √4375 - ( √3087 + √4732 - √2268)

Answer 1

1. √1805 - (√1620-√845) - √720 =
=19 √5 - (18√5-13√5) - 12√5 =
=19 √5 - 5√5 - 12√5 =
=2√5

2. √160 - (√810 - √9610 + √6760)=
= 4√10 - (9√10 - 31√10 + 26√10)=
= 4√10 - 4√10=0

3. √4375 - ( √3087 + √4732 - √2268)=
=25√7 - (21√7 + 26√7 - 18√7)=
=25√7 - 29√7 =
=-4√7