Bonjour pouvez vous m aider ex 25 merci bcp

Bonjour

a = 7/5

b = - 3/10

c = - 4

1. R = ab + c

R = 7/5 * (- 3/10) + (- 4)

R = - 21/50 - 4

R = - 21/50 - (4 * 50) / (1 * 50)

R = - 21/50 - 200/50

R = - 271/50

2. S = ab - bc

S = 7/5 * (- 3/10) - (- 3/10) * (- 4)

S = - 21/50 - 12/10

S = - 21/50 - (12 x 5) / (10 x 5)

S = - 21/50 - 60/50

S = - 81/50

3. T = (a + b) (a + c)

T = (7/5 - 3/10) (7/5 - 4)

T = [(7 x 2) / (5 x 2) - 3/10] [7/5 - (4 x 5) / (1 x 5)]

T = (14/10 - 3/10) (7/5 - 20/5)

T = 11/10 * (- 13/5)

T = - 143/50.