3x(2√5+1)+5x(2√3-1) 5√15-3√15-2x15√5-2x15√3
__________________ : ______________________ =
15 15√15
6√5+3+10√3-5 15√15
=_______________ x ___________________ =
15 2√15-30√5-30√3
√15
=2(3√5+5√3-1) x _______________ =
2(√15-15√5-15√3)
3·5√3+5·3√5-√15 15√3+15√3-√15
=____________________ =_______________ = - 1
√15-15√5-15√3 √15-15√5-15√3
b)
5 6√2+3·10√2·√2-2·15√3·√3
___________ x _______________________ = (se reduc 5 cu 30)
5√6 +2√3 30√6
6√2+30·2-30·3 6 (√2+10-15) √2-5 √2-5
=_________________ = ______________ = ________ = _______ =-1/6
6√6 ( 5√6 +2√3 ) 6· (5√6²+2√18) 30+6√2 6 (√2+5)
