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developpe et réduis ces expression
A=3(2x-6)-(3-5x)
B=5-2y)-(-3y+7)
C=4(6+z)+(z-3)(2-z)
D=(2t-5)(3t+2)-(t au carre +6)
E=3(-2x+5)+(-2x+5)(x-3)
F=2a-5)(3-4a)-2(5-a)
G= -(3-4z)(z-2)
H= -5r(2-3r)+(-r-2)(2r+5)

1

Réponses

2013-11-27T20:54:11+01:00
A=3(2x-6)-(3-5x)
=6x-18-3+5x
=11x-21

B=(5-2y)-(-3y+7)
=5-2y+3y-7
=y-2

C=4(6+z)+(z-3)(2-z)
=24+4z+2z-z²-6+3z
=-z²+9z+18

D=(2t-5)(3t+2)-(t² +6)
=6t²+4t-15t-10-t²-6
=5t²-11t-16

E=3(-2x+5)+(-2x+5)(x-3)
=-6x+15-2x²+6x+5x-15
=-2x²+5x

F=(2a-5)(3-4a)-2(5-a)
=6a-8a²-15+20a-10+2a
=-8a²+28a-25

G= -(3-4z)(z-2)
=-(3z-6-4z²+8z)
=-3z+6+4z²-8z
=4z²-11z+6

H= -5r(2-3r)+(-r-2)(2r+5)
=-10r+15r²-2r²-5r-4r-10
=13r²-19r-10