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Bonsoir
je suppose qu'il s'agit de l'exercice du bas.
Donc
D = 4/9 -2 x 13+3/13-3
D = 4/9 - 2 x 16/10
D = 4/9 -32/10
D = 40/90 - 288/90
d = 248/90
D = 124/45
E = 18 -16+4/7
E = 2+4/7
E = 14/7+4/7
E = 18/7
F = Barre du haut = -7/35-10/35 : 49/49 -15/49
F = -17/35 : 34/49
F = -17/35 x 49/34
F = -1/5 x 7/2
F = -7/10
Exercice 4:
A=2x(x-2)+3(5-x)-15
A=2x^2-4x+15-3x-15
A=2x^2-7x
B=7x^2-(5-2x^2)+x(x+1)
B=7x^2-5+2x^2+x^2+x
B=10x^2+x-5
C=2x-(x^2+x+1)+2x(2-x)
C=2x-x^2-x-1+4x-2x^2
C=-3x^2+5x-1
Exercice 5:
D=(4/9)-2((13+3)/(13-3))
D=(4/9)-2*(16/10)
D=(4/9)-(2*16)/(2*5)
D=(4/9)-(16/5)
D=(20/45)-(144/45)
D=-124/45
E=18-16:(4/7)
E=18-16*7/4
E=18-4*4*7/4
E=18-28=-10
F=((-1/5)-(2/7))/(1-(15/49)
F=((-7/35)-(10/35))/((49/49)-(15/49))
F=(-17/35)/(34/49)
F=-(17/35)*(49/34)
F=-(17/35)/(49/2*17)
F=-49/70
A=2x(x-2)+3(5-x)-15
A=2x^2-4x+15-3x-15
A=2x^2-7x
B=7x^2-(5-2x^2)+x(x+1)
B=7x^2-5+2x^2+x^2+x
B=10x^2+x-5
C=2x-(x^2+x+1)+2x(2-x)
C=2x-x^2-x-1+4x-2x^2
C=-3x^2+5x-1
Exercice 5:
D=(4/9)-2((13+3)/(13-3))
D=(4/9)-2*(16/10)
D=(4/9)-(2*16)/(2*5)
D=(4/9)-(16/5)
D=(20/45)-(144/45)
D=-124/45
E=18-16:(4/7)
E=18-16*7/4
E=18-4*4*7/4
E=18-28=-10
F=((-1/5)-(2/7))/(1-(15/49)
F=((-7/35)-(10/35))/((49/49)-(15/49))
F=(-17/35)/(34/49)
F=-(17/35)*(49/34)
F=-(17/35)/(49/2*17)
F=-49/70