Question

1.Calculați:
a) |-20+12|
b) -8-(-6+10)
c) -18+(-6+1)
2. Comparati numerele m si n,stiind ca m= -12-6 si n=-1-2-3-4-5
3. Scrieti valoarea de adevar a fiecareia dintre propozitiile:
a)-6 apartine multimii numerelor naturale
b)-7>-5
c) 4 apartine multimii numerelor intregi
d)-|-2-4|=6
4.a)Scrieti numarul -3 ca suma de doua numere intregi negative;
b) Scrieti numarul -3 ca diferenta de doua numere intregi negative
5. Calculati: -18-2{15-4-[10-(8-5)+(-3+9)]}
6.Determinati multimea A={x apartine multimii numerelor intregi | |x|=4 sau |x|=9}
7. Calculati:
a) 1-2+3-4+5-6+...+21-22
b) 1-2-3+4+5-6-7+8+8-10-11+12+...+61-62-63+64
VĂ ROOG...

Answer 1

1.a) |-20+12| = |-8| = 8
b)-8-(-6+10) = -8+6-10 = -2-10 = -12
c)-18+(-6+1) = -18 + (-5) = -23
2. m=-12-6 => m=-18
n=-1-2-3-4-5 => n=-15
-18 < -15 ( m < n)
3.a)-6=N (fals) (-6= Z)
b)-7>-5 (fals) (-7 <-5)
c)4=Z (adevarat)
d)-|-2-4|=6 => -|-6| => -6 (fals)
4.a)-1+(-2)=-3
b)-1-2=3
5.-18-2 {15-4[10-(8-5)+(-3+9)]}=
-18-2 [15-4 (10-3+6)]=
-18-2 (15-4×13 )=
-18-2 (15-52)=
-18-2×(- 38)=
-18+76= 58
6.|x|=4 sau |x|=9
A={-4,-9,4,9}
7.a)1-2+3-4+5-6+...+21-22=
-1+-1+-1+...-1 (de 11 ori)
-1×11= -11
b)1-2-3+4+5-6-7+8+8-10-11+12+...+61-62-63+64=
-4+4+-8+8+-12+12+...-64+64= (se simplifica)
= 0