Question

calcule o valor de x na soma
2x + 2x/3 + 2x/9 +... = 5

Answer 1

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2x + 2x/3 + 2x/9 +... = 5

u1 = 2
u2 = 2/3
q = u2/u1 = (2/3)/2 = 1/3

soma infinita
Sn = u1/(1 - q)
Sn = 2/(1 - 1/3) = 2/(2/3) = 3
3x = 5

x = 5/3