Question

Doar exercițiul 18 Vă rog frumos

Answer 1

Teorie:
$a^{n}=a*a*...*a$ (de n ori)   ex: $2^{4}$ =2*2*2*2=16 
$a^{m}* a^{n}= a^{m+n}$
$a^{n}: a^{m}= \frac{ a^{n} }{ a^{m} }= a^{n-m}$
$(a^{n})^{m}= a^{n*m}$
$a^{n}* b^{n} =(a*b)^{n}$
Sfarsit Teorie

 $3^{25}:3^{23}=3^{25-23}=3^{2}=9$
 $15^{2}=15*15=225$
 $6^{2}=6*6=36$

Restul sunt calcule algebrice, pe care sunt sigur ca le stii din clasa a 3-a

Answer 2

a) 12[25+7*3² -38]-500=
12*(25+7*9-38)-500=
12*50-500=
600-500=100

b) 2015:[15²+6²x(275:11-17)-22*5]=
2015:[15²+6²x(25-11)-110]=
2015:[15²+6²x14-110]=
2015:[225+36x14-110]=
2015:[225+504-110]=
2015:[729-110]=
2015:619=3,255...
1857
____
1580
1238
____
=3420
  3095
______
  =3250
    3095
  _____
    =1550
      1238
   _______
       =312