Question

Aflati primul termen si ratia progresii aritmetice (an) n > sau egal cu 1 daca 3a1-4a7=87
a4-a10=24

AM NEVOIE URGENT!!!!!!!

Answer 1

Răspuns:

) a4=10, a7=19

b) a3= -4, S15= -285

c) {a2+a5-a8=10

{a1=a6=17

d) {a4+a8=30

{10a1-4a7= -45

e) {a2+a6+a9=45

{a3+a7+a10=54

f) {S3=12

{S6=51

g) {S2-S4+a2=14

{S3+a3=17