a)transformam radicalii
=(4·3√3 - 5·2√6 +3·4√3)÷(-√3)-(-12√2÷√2 +20÷√2)
=(12√3-10√6+12√3)÷(-√3) - (-12 +20√2 /2)
=(-10√6)÷(-√3) - (-12+10√2)
=10√2+12-10√2
=12
b)(3·5√5-2·3√5)÷√5 - (2·2√5+3·4√5)÷(-√5)
=(15√5-6√5)÷√5 - (4√5+12√5)÷(-√5)
=9√5÷√5 +16√5÷√5
=9+16
=25
