* signifie multiplié par
Exercice 27
A = x²+3x-1
a. x = √7
A = (√7)² + 3*√7-1
A = 7 +3√7 -1
A = 6+3√7
b. x = -√7
A = (-√7)² + 3*-√7-1
A = 7 -3√7 -1
A = 6-3√7
Exercice 27
A = x²+3x+4
a. x = √2
A = (√2)² +3*√2 + 4
A = 2+3√2+4
A = 6+3√2
b. x = -√5
A = (-√5)² +3*-√5 + 4
A = 5-3√5+4
A = 9-3√5
Exercice 30
A = 4x-3√2
a. x = -3
A = 4*-3 - 3√2
A = -12 - 3√2
b. x = 5√2
A = 4*5√2 -3√2
A = 20√2 - 3√2
A = 17√2
c. x = 5-2√2
A = 4(5-2√2) -3√2
A = 4*5 -4*2√2 - 3√2
A = 20-8√2 -3√2
A = 20-11√2
