Question

a=rad(8) si b = rad(2)+1 supra rad(2)-1            a) verificati daca a+2 supra a-2=b                         AJUTATINA va rog

Answer 1

a=√8= 2√2
b=√2+1 pe √2-1
a+2 pe a-2 = b
2√2 + 2 pe 2√2 - 2= 2√2+1 pe 2√2 -1

Answer 2

a=√8= 2√2

b=(√2+1)/(√2-1)  se rationalizeaza

b=(√2+1)²/2-1

b=(2+2√2+1)/1

b=3+2√2

(a+2)/(a-2)=b

(√8+2)/(√8-2)=3+2√2    se rationalizeaza

(√8+2)²/8-4=3+2√2

(8+4√8+4)/4= 3+2√2

(12+8√2)/4 =3+2√2  aducem la acelasi numitor

12+8√2=12+8√2