1)
A = √32 - 5√18 - 5√8
= √16*√2 - 5*√9*√2 - 5*√4*√2
= 4√2 - 5*3*√2 - 5*2*√2
= 4√2 - 15√2 - 10√2
= -21√2
B = √8 * √18 * √32
= √(8*18*32)
= √4608
= √2304 * √2
= 48√2
2)
C = (4√5 + √3)²
= (4√5)² + 2*4√5*√3 + (√3)²
= 16*5 + 8*√15 + 3
= 80 + 3 + 8√15
= 83 + 8√15
D = (2√7 + 3√2)²
= (2√7)² + 2*2√7*3√2 + (3√2)²
= 4*7 + 12√14 + 9*2
= 28 + 12√14 + 18
= 46 + 12√14
3)
E = (3 - 2√2)(3 + 2√2) est de la forme (a-b)(a+b)=a²-b²
= 3² - (2√2)²
= 9 - 4*2
= 1
F = [tex] \dfrac{48 \sqrt{45}}{9 \sqrt{80}}= \dfrac{48* \sqrt{9}* \sqrt{5}}{9* \sqrt{16}* \sqrt{5}}= \dfrac{48*3* \sqrt{5}}{9*4* \sqrt{5}}= \dfrac{144}{36} = 4[/tex]
