### Find the direction of the velocity vector at the instant

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##### Reference no: EM13530889

The position vector,r, in meters, of a particle moving in the x-y plane, is giving by the following equation: r=i(2t^2-8t 12)+j(2t^3-18t^2+48t+25), where -10<t<+10.

i) find the time or times when the object is instantaneously at rest.

ii) find the direction of the velocity vector at the instant when the acceleration vector is parallel to the x-axis.

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