Question

6. Efectuați:
a) {+ 5 - 8 + 3+ [+ 6 - 3 + 4 + (+ 4 - 7 + 1)]} + 9-7;
b) {-2 + 4 + 6 + [-5 + 1 + 2 + (- 6+9 -2)]} + 3 - 8;
c) - 1 + 3 + {+ 1 - 3 - 5+ [-7 - 4+ 5+ (- 6 + 2 - 4)]};
d) 10-6 + 8 + {+ 3 - 6 - 5+ [-1 + 4 - 3+ (-7 + 5 - 2)]};
e) - 2 + 9 + 4- 6 + 4 - 3+ [+ 5 - 3 - 6 + (+ 7 - 9 - 1)]};
f) -7 + 2 + 5 + {-1 + 4 - 2 + [-3 + 6 -5 + (-9 + 8 - 2)]}.​

Answer 1

a) {5-8+3+[6-3+4+(4-7+1)]}+9-7=5

1. 4-7+1=-4

2. 6-3+4-4=3

3. 5-8+3+3=3

4. 3+9-7=5

b) {-2+4+6+[-5+1+2+(-6+9-2)]}+3-8=2 1. -6+9-2=1

2. -5+1+2+1=-1

3. -2+4+6-1=7

4. 7+3-8=2

c) -1+3+{1-3-5+[-7-4+5+(-6+2-4)]}=-19

1. -6+2-4=-8

2. -7-4+5-8=-14

3. 1-3-5-14=-21

4. -1+3-21=-19

d) 10-6+8+{3-6-5+[-1+4-3+(-7+5-2)]}=0

1. -7+5-2=-4

2. -1+4-3-4=-4

3. 3-6-5-4=-12

4. 10-6+8-12=0

e) -2+9+4-6+4-3+[5-3-6+(7-9-1)]=-1

1. 7-9-1=-3

2. 5-3-6-3=-7

3. -2+9+4-6+4-3-7=-1

f) -7+2+5+{-1+4-2+[-3+6-5+(-9+8-2)]}=-4

1. -9+8-2=-3

2. -3+6-5-3=-5

3. -1+4-2-5=-4

4. -7+2+5-4=-4