Soluciones a las actividades de cada epígrafe

4
Soluciones a las actividades de cada epígrafe
PÁGINA 87
Pág. 1
1 Escribe en forma de producto las siguientes expresiones:
a) +(–7) + (–7) + (–7)
b) –(+3) – (+3) – (+3) – (+3)
c) +(+2) + (+2) + (+2)
d) –(–3) – (–3) – (–3) – (–3) – (–3)
e) +(–20) + (–20) + (–20) + (–20)
a) +(–7) + (–7) + (–7) = (+3) · (–7)
b) –(+3) – (+3) – (+3) – (+3) = (–4) · (–3)
c) +(+2) + (+2) + (+2) = (+3) · (+2)
d) –(–3) – (–3) – (–3) – (–3) – (–3) = (–5) · (–3)
e) +(–20) + (–20) + (–20) + (–20) = (+4) · (–20)
2 Calcula estos productos:
a) 3 · (–2)
b) 4 · (+5)
c) 8 · (–6)
d) –5 · (+3)
e) –2 · (–4)
f ) –6 · (+3)
g) (–4) · (+7)
h) (+2) · (+6)
i) (–5) · (–7)
j) (+3) · (–8)
k) (–9) · (–3)
l) (–6) · (+4)
a) 3 · (–2) = –6
b) 4 · (+5) = +20
c) 8 · (–6) = –48
d) –5 · (+3) = –15
e) –2 · (–4) = +8
f ) –6 · (+3) = –18
g) (–4) · (+7) = –28
h) (+2) · (+6) = +12
i) (–5) · (–7) = +35
j) (+3) · (–8) = –24
k) (–9) · (–3) = +27
l) (–6) · (+4) = –24
3 Copia y completa el factor desconocido.
a) (–6) ·
= –18
b) (+8) ·
= –24
c) (–7) ·
= +35
d) (+15) ·
= +60
a) (–6) · (+3) = –18
b) (+8) · (–3) = –24
c) (–7) · (–5) = +35
d) (+15) · (+4) = +60
Unidad 4. Los números enteros
4
Soluciones a las actividades de cada epígrafe
4 Calcula el cociente entero, si existe.
Pág. 2
a) (–8) : (+2)
b) (+20) : (–10)
c) (–12) : (–4)
d) (– 4) : (+3)
e) (+20) : (–7)
f ) (–1) : (+6)
g) (–15) : (–3)
h) (+32) : (+8)
i) (–36) : (+9)
j) (+42) : (–7)
k) (–48) : (–8)
l) (+54) : (+6)
a) (–8) : (+2) = –4
b) (+20) : (–10)= –2
c) (–12) : (–4) = +3
d) (–4) : (+3) No entero
e) (+20) : (–7) No entero
f ) (–1) : (+6) No entero
g) (–15) : (–3) = +5
h) (+32) : (+8) = +4
i) (–36) : (+9) = –4
j) (+42) : (–7) = –6
k) (–48) : (–8) = +6
l) (+54) : (+6) = +9
5 Escribe:
a) Tres divisiones de enteros cuyo cociente sea entero.
b) Tres divisiones de enteros cuyo cociente no sea entero.
Solución abierta.
6 Calcula.
a) (+3) · (–5) · (+2)
b) (–4) · (–1) · (+6)
c) (–2) · (–7) · (–2)
d) (+5) · (–4) · (–3)
a) (+3) · (–5) · (+2) = –30
b) (–4) · (–1) · (+6) = +24
c) (–2) · (–7) · (–2) = –28
d) (+5) · (–4) · (–3) = +60
7 Opera.
a) [(+80) : (–8)] : (–5)
b) [(–70) : (–2)] : (–7)
c) (+50) : [(–30) : (+6)]
d) (–40) : [(+24) : (+3)]
a) [(+80) : (–8)] : (–5) = [–10] : (–5) = +2
b) [(–70) : (–2)] : (–7) = [+35] : (–7) = –5
c) (+50) : [(–30) : (+6)] = (+50) : [–5] = –10
d) (– 40) : [(+24) : (+3)] = (–40) : [+8] = –5
8 Resuelto en el libro del alumno.
Unidad 4. Los números enteros
4
Soluciones a las actividades de cada epígrafe
9 Opera como en el ejercicio resuelto anterior.
a) [(+6) · (–4)] : (–3)
b) [(–15) · (–2)] : (+6)
c) (–5) · [(+12) : (–3)]
d) [(–5) · (+12)] : (–3)
a) [(+6) · (–4)] : (–3) = [–24] : (–3) = +8
b) [(–15) · (–2)] : (+6) = [+30] : (+6) = +5
c) (–5) · [(+12) : (–3)] = (–5) · [–4] = +20
d) [(–5) · (+12)] : (–3) = [–60] : (–3) = +20
10 Calcula.
a) 5 · (–4) + 2 · (–3)
b) 20 : (–5) – 8 : (+2)
c) 2 · (–8) – 3 · (–7) – 4 · (+3)
d) 6 : (+2) + 5 · (–3) – 12 : (–4)
a) 5 · (–4) + 2 · (–3) = –26
b) 20 : (–5) – 8 : (+2) = –8
c) 2 · (–8) – 3 · (–7) – 4 · (+3) = –7
d) 6 : (+2) + 5 · (–3) – 12 : (–4) = –9
11 Opera.
a) (–8) · (+2) + (–5) · (–3)
b) (+40) : (–8) – (–30) : (+6)
c) (–2) · (–9) + (–24) : (–3) – (–6) · (–4)
d) (+27) : (–3) – (+3) · (–5) – (–6) · (–2)
a) (–8) · (+2) + (–5) · (–3) = –1
b) (+40) : (–8) – (–30) : (+6) = 0
c) (–2) · (–9) + (–24) : (–3) – (–6) · (–4) = 2
d) (+27) : (–3) – (+3) · (–5) – (–6) · (–2) = –6
12 Resuelto en el libro del alumno.
13 Calcula como en el ejercicio resuelto anterior.
a) (–3) · [(–2) + (–4)]
b) (+4) · [(–5) + (+2)]
c) (+6) : [(+5) – (+7)]
d) (–20) : [(–6) – (–2)]
e) [(–8) + (+7)] · (–3)
f ) [(–9) + (–3)] : (+6)
a) (–3) · [(–2) + (–4)] = (–3) · [–2 – 4] = (–3) · [–6] = +18
b) (+4) · [(–5) + (+2)] = (+4) · [–5 + 2] = (+4) · [–3] = –12
c) (+6) : [(+5) – (+7)] = (+6) : [+5 – 7] = (+6) : [–2] = –3
d) (–20) : [(–6) – (–2)] = (–20) : [–6 + 2] = (–20) : [–4] = +5
e) [(–8) + (+7)] · (–3) = [–8 + 7] · (–3) = [–1] · (–3) = +3
f ) [(–9) + (–3)] : (+6) = [–9 – 3] : (+6) = [–12] : (+6) = –2
Unidad 4. Los números enteros
Pág. 3
4
Soluciones a las actividades de cada epígrafe
14 Resuelto en el libro del alumno.
Pág. 4
15 Opera como en el ejercicio resuelto anterior.
a) 19 – (–3) · [5 – (+8)]
b) 12 + (–5) · [8 + (–9)]
c) 12 – [13 – (–7)] : (–5)
d) 10 – (+20) : [7 + (–3)]
e) (–2) · (5 – 7) – (–3) · (8 – 6)
f ) (9 – 6) · (–2) + (13 + 3) : (–4)
a) 19 – (–3) · [5 – (+8)] = 19 – (–3) · [–3] = 19 – (+9) = 19 – 9 = 10
b) 12 + (–5) · [8 + (–9)] = 12 + (–5) · [–1] = 12 + (+5) = 12 + 5 = 17
c) 12 – [13 – (–7)] : (–5) = 12 – [+20] : (–5) = 12 – (–4) = 12 + 4 = 16
d) 10 – (+20) : [7 + (–3)] = 10 – (+20) : [+4] = 10 – (+5) = 10 – 5 = 5
e) (–2) · (5 – 7) – (–3) · (8 – 6) = (–2) · (–2) – (–3) · (+2) = (+4) – (–6) = 4 + 6 = 10
f ) (9 – 6) · (–2) + (13 + 3) : (–4) = (+3) · (–2) + (+16) : (–4) =
= (–6) + (–4) = –6 – 4 = –10
Unidad 4. Los números enteros