Exercices sur le chapitre 7 Exercices sur le chapitre 7
Exercices donnés en classe A=–8y6y
A=–2y B=–5x –12x
B=–17x C=5x –16x
C=–11x D=–8x2–7x2 D=–15x2
E=3x2–2x E=on peut pas
F=– x6x F=–1x6x F=5x
G=y2–3y2 G=1y2–3y2 G=–2y2
H=x –11x H=1x –11x H=–10x
I=–6x2– x2 I=–6x2–1x2 I=–7x2
J=43x2 J=on peut pas !
Correction 1 page 114
A=6x3x=9x ; B=82x (impossible) ; C=4x5x=9x ; D=5x3 impossible ; E=4x22x2=6x2 ; F=5x4x2 (impossible) ; G=9x24x2=13x2 ;
H=7x23x2=10x2 ; I=9x2x2=10x2
J=5–9x (impossible) ; K=5x –7x=–2x ; L=–3x –6x=–9x ;
M=–8x2x=–6x ; N=–8x2–6x2=–14x2 ; P=43x2 (impossible) ; R=–5x2–7x (impossible) ; S=4x2–6x2=–2x2 ; T=–5x2– x2=–6x2 Calcul mental
1/ –2x5x=3x 2/ 3–9=–6
3/ x2–5x2=–4x2 (+1 et -5) 4/ 34x=impossible
5/ –5x –4x=–9x
6/ 7x2–11x2=–4x2 (+7 et -11) 7/ – x – x=–2x
8/ –8x8x=0
9/ 2x3x2=impossible 10/ –8x13x=5x Exercice donné en classe
12x –72 (impossible) B=7 y12–13y B=7 y –13y12 B=–6y12 C=10–8d3 C=103–8d C=13–8d D=8– xx25x D=–1x5x8x2 D=4x8x2 D=x24x8
Exercice 2 b. page 114 G=8m –10m4m G=–2m4m G=2m
I=–8m –2m –5m I=–10m –5m I=–15m
K=2m –7m24m2 K=2m –3m2
H=5m –4m8m H=1m8m H=9m
J=6m25m2–8m2 J=11m2–8m2 J=3m2
L=–7m25m2–3m2 L=–2m2–3m2 L=–5m2 Exercice 9 a. page 114
A=52x7
A=5×2x5×7 A=10x35 B=52x×3 B=3×53×2x B=156x C=x3x7
C=x×3xx×7 C=3x27x D=4x2x6
D=4x×2x4x×6 D=8x224x
Exercice 10 page 114 a.
A=42x –7
A=8x –28
B=–3–2x5
B=6x –15
C=–6–3x –7
C=18x –42 D–2x4×3
D=–6x12
b.
E=– x3x4 F=2x4x –5
G=–3x–2–4x H=5x –4×4x
Exercice 46 page 118 A=7x5x343x2
A=7x×5x7x×34×3x4×2 A=35x221x12x8
A=35x233x8
B=8x3x3–5x7x6
B=8x×3x8x×3–5x×7x –5x×6 B=24x224x –35x2–30x
B=–11x2–6x
C=–42x –54x63x D=–639x–3x2x –7
Calcul mental
1/ –2x9x=7x 2/ –2x –1x=–6x 3/ –8x10x=2x 4/ 3x – x=2x
5/ –11xx=–10x
6/ –2×–5x=10x 7/ – x×– x=x2 8/ 5x×–3x=–15x2 9/ 2x×–4x=–8x2 10/ –5x×–6x=30x2 Correction du devoir maison
• Exercice 12 page 115 A=5x2–6x4
A=5x2–6x –4 A=– x –2
B=–2x34x –5
B=–5x34x –5 B=–1x –2
B=– x –2 C=–3x –4––8x3
C=–3x –48x –3 C=5x –7
D=5x23–8x2–2x3
D=5x23–8x22x –3 D=–3x22x
E=6x2–3x5–4x2–3x –4
E=6x2–3x5–4x2–3x –4 E=2x2–6x1
En plus
I=7x –5x8
I=7x –5x –8 I=2x –8
J=5x2–9–8xx2–4
J=5x2–9–8x – x24 J=4x2–5–8x
K=8––7x5x8 K=87– x5x8 K=234x
L=–x58– x
L=– x –58– x L=–2x3 Calcul mental
1/ –2x5x=3x 2/ x×–5x=–5x2 3/ –5x –8x=–13x 4/ –3x×2x=–6x2 5/ – x – x=–2x
6/ – xx=0x=0 7/ –7x×–8x=56x2 8/ 12x2–17x2=–5x2 9/ 2x7x2=on peut pas !!
10/ – x×– x=x2
• Exercice 13 page 115
A=23c –5–4c3×6 B=5–4c2–3c –4×2
B=5×–4c5×2–3c×2–−4×2 B=–20c10–6c8
B=–26c18
C=–25c3––4c7×3 C=–2×5c –2×3–3×–4c–3×7 C=–10c –612c –21
C=2c –27
D=6c2×3–2c7×4
Exercice 30 page 116
A=5–3x6–3x4x –7
A=5×–3x5×6–3x×4x –3x×–7
A=–15x30–12x221x A=6x –12x230
C=5x –3x –4 C=5x –3x4 C=2x4
Exercices développement double A=7x –35x –8
B=–2x8– x9
C=8–4x–5x –11
D=–6x –87x –5
Exercice 14 page 115 (correction) A=3x45x2
A=3x×5x3x×2 4×5x4×2 A=15x26x20x8
A=15x226x8 B=52x3x7
B=5×3x5×72x×3x2x×7 B=15x356x214x
B=29x356x2 B=6x229x35 C=4x532x
C=4x×34x×2x5×35×2x C=12x8x21510x
C=8x222x15 E=5x342x E=5x3×43×2x E=5x126x E=11x12
D=5x342x
D=5x×45x×2x3×43×2x D=20x10x2126x
D=10x226x12 F=7x27x2
F=7x×7x7x×2 2×7x2×2 F=49x214x14x4
F=49x228x4
Exercices donnés en classe A=–82x–5x3
...
A=–10x246x –24
B=–38x–5x –7
...
B=–40x2–41x21 C=–5x –78–3x
…
C=15x2–19x –56
D=– t11–8t –7
…
D=8t2–81t –77 Calcul mental
1/ –83=–5 2/ –6×–2=12 3/ 9–15=–6 4/ 5×–11=–55 5/ –7–18=–25
6/ –7x12x=5x 7/ 15x –11x=4x 8/ –2x×–3x=6x2 9/ 7x×–5=–35x 10/ x2x –5=2x2–5