Aussie Maths & Science Teachers: Save your time with SmarterEd
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(Using elimination)`
`a < 0. text(Cannot be C.)`
`r < -1. text(Successive terms change sign and)`
`text(increase exponentially.)`
`text(Cannot be A, 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,)`
`text(i.e.)\ \ |\ r\ | < 1.`
`text (Only one choice satisfies these conditions.)`
`rArr B`