Bonjour j'aurai besoin d'aide pour cette exercice de mathématique voici ci-dessous l'énoncé : 1) Calculer A= 1-5 x pour : * x=0 * x=1 *x=2 2) calculer B= x²- 2

Bonjour,

1) Calculer A = 1 - 5x pour :

* x=0

A = 1 - 5x

A = 1 - 5 * 0

A = 1 - 0

A = 1

* x=1

A = 1 - 5x

A = 1 - 5 * 1

A = 1 - 5

A = - 4

*x=2

A = 1 - 5x

A = 1 - 5 * 2

A = 1 - 10

A = - 9

2) Calculer B = x²- 2x pour  :

x=1

B = x²- 2x

B = 1² - 2 * 1

B = 1 - 2

B = - 1

x=2

B = x²- 2x

B = 2² - 2 * 2

B = 4 - 4

B = 0

x=4

B = x²- 2x

B = 4² - 2 * 4

B = 16 - 8

B = 8

3)

Calculer C = 7 - 4x pour  :

x = 5

C = 7 - 4x

C = 7 - 4 * 5

C = 7 - 20

C = - 13

x=3/4

C = 7 - 4x

C = 7 - 4 * 3/4

C = 7 - 12/4

C = 7 - 3

C = 4

x=2/5

C = 7 - 4x

C = 7 - 4 * 2/5

C = 7 - 8/5

C = 35/5 - 8/5

C = 27/5

Bonjour,

Rien de bien compliqué, il suffit de remplacer x par la valeur donnée.

1) A = 1 - 5x

→ 1 - ( 5 * 0 ) = 1 - 0 = 1

→ 1 - ( 5 * 1 ) = 1 - 5 = (-4)

→ 1 - ( 5 * 2 ) = 1 - 10 = (-9)

2) B = x² - 2x

→ 1² - ( 2 * 1 ) = 1 - 2 = (-1)

→ 2² - ( 2 * 2 ) = 4 - 4 = 0

→ 4² - ( 2 * 4 ) = 16 - 8 = 8

3) → 7 - ( 4 * 5 ) = 7 - 20 = (-13)

→ 7 - ( 3/4 * 4 ) = 7 - 12/4 = 7 - 3 = 4

→ 7 - ( 2/5 * 4 ) = 7 - 8/5 = 35/5 - 8/5 = 27/5

Bonne journée :)