GRAPHS, FUR1 2004 VCAA 9 MC

The graph above represents a relationship `y = kx^3` for `x ≥ 0`.
A graph that shows this relationship when `y` is plotted against `x` is

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`A`

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`y = kx^3\ text(for)\ x ≥ 0`

`text(From the graph,)\ (8, 1)\ text(fits this line)`

`:.\ y = 1\ text(when)\ x^3 = 8`

`text(Sub)\ y = 1, x^3 = 8\ text(into)\ y = kx^3`

`1`	`= k(8)`
`k`	`= 1/8`

`:.\ y = 1/8 x^3\ \ \ … \ text{(i)}`

`text(Consider)\ A`

`text{ Sub (2, 1) into (i)}`

`:.\ text(LHS = RHS)`

`text(Similarly)\ B, C, D, E\ text(can be eliminated)`

`=> A`