Question

determinar o n° de termos da pa 1,4,7,...298

Answer 1

an = a1 + (n - 1) . r
298 = 1 + (n - 1) . 3
298 = 1 + 3n - 3
298 = -2 + 3n
298 + 2 = 3n
300 = 3n
300/3 = n
100 = n

A PA tem 100 termos.

Answer 2

Pa(1.,4,7,.....298) an=a1+(n-1).r 298=1+(n-1).3 298-1=3n-3 297+3=3n 300=3n n=300/3 n=100