1 > 2x-5=6 2x=11 x=11/5 =2.2
3(2x-7)=0 6x-21=0 6x=21 x=21/6= 3.5
2(x-5) = 6 2x-10=6 2x= 16 x=16/2=8
4x^2=100 (4x puissance 2 = 100) x^2 = 100/4=25 donc x= racine de 25 =5
2>(5 + racine 2 )^2 forme (a+b)^2 = a^2+2ab+b^2
= 25+10racine de 2+2= 27+10racine de 2 =41.14
(5-racine de 2)^2 =25-10racine de2+2=27-10racine de 2 =12.86
(racine de 5 +2)^2 = 5 +10racine de5 +4= 9 +10racine de5
(5+racine de 2) (5-racine de 2) forme (a+b) (a-b) = a^2-b^2
(5+racine de 2) (5-racine de 2) =25-2=23
