Question

Ajutor!Rezolvati va rog exercitiile date.Este Urgent

Answer 1

2)

$\it = \sqrt{16\cdot2} -\sqrt{25\cdot2}+\sqrt{4\cdot2}-\sqrt{49\cdot2}+\sqrt{121\cdot2}=$

$\it = 4\sqrt2 - 5\sqrt2+ 2\sqrt2- 7\sqrt2+ 11\sqrt2 = 17\sqrt2-12\sqrt2 =5\sqrt2.$

Answer 2

a=(√(3+2)+3√3)*√3*5-2√3
a=(√5+3√3)*5√3-2√3
a=5√15+45-2√3
Iar b:
b=√(11-6√2) /3√5-√10
Rezolvam numaratorul separat (scopul este sa formam un patrat perfect):
√(11-6√2)=√(9+2-6√2)=√(3-√2)² =|3-√2| =3-√2
Revenim:
b=3-√2/√5(3-√2) 
Se simplifica si va ramane:
b=1/√5
Daca rationalizam cu √5 obtinem:
b=√5/5