bonjour

au lycée A, B, C  F et I , tu fais

D = √2/ 3 √8

D =  (√2  x  3 √8 ) / ( 3 √8)²

D =  3 √16 / 72

D =  √16/24

E = 2 / √2 - √ 2

E =  ( 2 x √2) / ( √2)² -  √2

E = ( 2 √2 / 2 ) - √2

E =   √2 - √2  = 0

H = ( 5 √8 - 2 √2) ²

H = 200 - 20√16 + 8

H = 200 - 80 + 8 = 128

Réponse :

Explications étape par étape :

Bonjour

A = 2/3 -1/6

A = 4/6 - 1/6

A =3/6

A = 1/2

B = - 8 × 0.625 = - 5

C = 14/5 × 35/9

C = (14 × 35) / (5× 9)

C = (14 × 7 × 5)/(5×9)

C = 98/9

D = √√2 / (3√8)

D = √2/ (3√4√2)

D= √2/ (3×2√2)

D =1/6

E = 2/√2 - √2

E = 2√2/(√2√2) - √2

E =2√2/ 2 - √2

E = √2 - √2

E = 0

F = (13/2 -4/5) ×7/3

F = (65/10- 8/10) × 7/3

F = 57/10 × 7/3

F = (57×7)/(10×3)

F = (19×3×7)/(10×3)

F = 133/10

G = (1 - √2)² - (1 +√2)² est de la forme a² - b² = (a - b ) (a + b) avec a² = (1 - √2)² et b² = (1 + √2)² donc a = 1 -√2 et b = 1 + √2

G = (1 - √2 - (1 + √2))( 1 -√2 + 1 +√2)

G = (1 - √2 - 1 - √2) (2)

G = - 2 √2 × 2

G = - 4 √2

H = (5√8 - 2√2)² est de la forme (a - b)² = a - 2 ab + b² avec a = 5√8 et b =2√2

a = 5√4√2=5×2√2= 10√2

donc H = (10√2)² - 2 × 10 √2 × 2√2 + (2√2)²

H = 100 √2² - 40 √2² + 4√2²

H = 100×2 - 40×2 +4×2

H = 200 - 80 + 8

H = 128

I =(13 -1/2)/(-5/4 + 1/3)

I = (26/2-1/2) / (-15/12 +4/12)

I = (25/2) / (-11/12)

I = 25/2 × 12/(-11)

I = (25×12) / (2× (-11))

I = (25 ×2 ×6)/ (2× (-11))

I = - 150/11