Question

scoate ti factorii de sub radicali , rationalizati numitorii si apoi calculati :
a) 3\rad 32 - 5 \ 2 rad 50
b ) 5 \ 2 rad 12 + 2 \ rad75
c ) 2 \ rad 20 - 3\ 2 rad 45
d) 7 \ rad 24 - 1 \ 2 rad 54 va rogg repede

Answer 1

a) 3/√32 - 5/2√50 =
=3/4√2 - 5/10√2 =
=3/4√2 - 1/2√2 =
=3√2/8 - √2/4 =
=(3√2-2√2)/8=
=√2/8

 b ) 5/2√12 + 2/√75=
=5/4√3 + 2/5√3=
=5√3/12 + 2√3/15=
=(25√3+ 8√3)/60=
=33√3/60=
=11√3/20=

c ) 2/√20 - 3/ 2√45 =
=2/2√5 - 3/ 6√5 =
=2√5/10 - 3√5/30 =
=(6√5-3√5)/30=
=3√5/30 =
=√5/10

d) 7/√24 - 1/ 2√54=
=7/2√6-1/6√6=
=7√6/12-√6/36=
=(21√6-√6)/36=
=20√6/36=
=5√6/9