Sagot :
1.
a) (1+racine5)²=1+2*racine5+5=6+2*racine5
b) (racine3-5)²=3-10*racine3+25=22-10*racine3
c) (racine3+2)²=3+4*racine3+4=7+4*racine3
d) (7-racine11)²=49-14*racine11+11=60-14*racine11
etc ...
Voila :)
a. (1)²+2*1*√5+(√5)²
1+2√5+5
6+2√5
b.(√3)²-2*√3*5+(5)²
3-10√3+25
28-10√3
c. (√3)²+2*√3*2+(2)²
3+4√3+4
7+4√3
d. (7)²-2*7*√11+(√11)²
49-14√11+11
60-14√11
a.(2)²+2*2*2√5+(2√5)²
4+8√5+20
24+8√5
b. (3)²-2*3*5√2+(5√2)²
9-30√2+10
19-30√2
c. (5)²+2*5*2√3+(2√3)²
25+20√3+6
31+20√3
d. (4)²-2*4*3√2+(3√2)²
16-24√2+6
22-24√2
A= 2-√7+√7-7
-5
B= 3-√3+√3-1
2
C= 18-6√2+6√2-4
14
D= 20-6√5+6√5-6
14