Question

exercitiul 4 &&&&:***

Answer 1

a)Inainte,de,toate,rationalizam,numitorii,adica,inmutim,cu,√5,si,√20
√5(3x+1)/5=2√5(x+42)/20
20√5(3x+1)=10√5(x+42)
Se,simplifica,20√5,si,10√5,si,ramane
2(3x+1)=x+42
6x+2=x+42
6x-x=42-2
5x=40=>x=8∈R

b)y²+4y+4+y=9-6y+y²-5
5y+4=4-6y
5y+6y=4-4
11y=0=>y=0∈Q

Answer 2

Exercitiul 4.
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