Bonjour,

Exercice 3 demandé:

Ecrire sous forme...:

• [((2-√3)(1+√3))/ ((1-√3)(1+√3))]= (2+2√3-√3-3)/(1-√3+√3-3)= (-1+√3)/-2

= (1-√3)/2

• [ 1(√2-1)/ (√2+1)(√2-1) ]= (√2-1)/ (2+√2-√2-1)= (√2-1)/ 1= √2-1

Exercice 5 demandé:

Calculer:

(3/4 - 2√(12/12)+4/3= 3/4-2+1/3= (3x3-2x12+4x4)/12=(9-24+16)/12=  1/12

idem pour ce calcul, distribue, on obtient:

5/2 + 2 + 2/5= (5x5+2x10+2x2)/10=  49/10.

a-2+(1/a)=(axa-2xa+1)/a=(a²-2a+1)/a

a+2+(1/a)= ((axa+2xa+1)/a= (a²+2a+1)/a.