Question

27. Calculaţi:
asa a V-a
a) (1 + 2 +3 + ... +14) : (1 + 2 + 3 + ... + 6);
b) (1.2.3... . 15): (1 + 2 + 3 + ... + 15).​

Answer 1

a)(1+2+3+...+15)=(15*16)/2

=15*8=120

(1+2+3+4+5+6)= (6*7)/2=3*7=21

120:21=5,(714285)

b)In caz ca "(1.2.3.4.... .15)" inseamna inmultire, =>

(1*2*3*4*....*15):(1+2+3+4+...+15)=?

Avem mai sus ca (1+2+3+....+15)=120

(1*2*3*4*...*15):120=

Daca o luam la rand,

1*2=2

2*3=6

6*4=24

24*5=120

120*6=720

720*7=5040

5040*8=40320

40320*9=362880

362880*10=3628800

3628800*11=39916800

39916800*12=479001600

479001600*13=6227020800

6227020800*14=87178291200

87178291200*15=1307674368000

1307674368000:120=10897286400

Sper ca am inteles corect ce insemnau punctele acelea, daca da, aceasta e rezolvarea