a. [5/(3√2)+3√2/8-7/(12√2)]·8√2/15=
=[5√2/6+3√2/8-7√2/24]·8√2/15=
=[20√2/24+9√2/24-7√2/24]·8√2/15=
=22√2/24·8√2/15=
=22√2/3·√2/15=
=44/45
b. √2(2√2/27)-3/8·4√2/27=
=4/27-3/2·√2/27=
=(8-3√2)/54
sau daca 9/8 este tot sub radical
√2(2√2/27)-3/2√2·4√2/27=
=4/27-3√2/4·4√2/27=
=4/27-6/27=-2/27