Question

Arătaţi ca 3(2-√20)+ √180= 6

Answer 1

3(2-√20)+√180=6

desfacem paranteza

6-3√20+√180=6

acum vom introduce 3 sub radical

6-√3²*20+√180=6

6-√9*20+√180=6

6-√180+√180=6

observam ca -√180 si √180 sunt opuse, deci le eliminam

6=6 (A)

prin eliminare, rezulta un adevar, deci 3(2-√20)+ √180= 6 (A)