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The graph above shows the first six terms of a sequence.
This sequence could be
`D`
`text(Series is 1, 1, 1, …)`
`text(The only possibility within the choices)`
`text(is a geometric sequence where)\ \ r=1.`
`=> D`
The first term of a geometric sequence is `a`, where `a < 0`.
The common ratio of this sequence, `r`, is such that `r <-1`.
Which one of the following graphs best shows the first `10` terms of this sequence?
`B`
`text(By elimination:)`
`a < 0\ \ text{(eliminate C)}`
`r < -1\ \ \->\ text{successive terms change sign and increase exponentially.}`
`text{(eliminate A and D)}`
`=> B`
The graph above shows consecutive terms of a sequence.
The sequence could be
`B`
`text (As)\ \ n\ \ text (increases,) \ \ t_n →0.`
`:.\ text (Series is a GP with a limiting sum, where\ \ |\ r\ | < 1.`
`text (Only one choice satisfies these conditions.)`
`=> B`