In this question distance is in centimetre
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Particle X is moving along a straight line such that its displacement from a point A , after t seconds, is given by $ s_{\mathrm{X}}=24-t-5 t^{3} e^{-0.6 t}$,$ \quad 0 \leq t \leq 30$
This is shown in the following diagram.
1. Find the value of t when particle X first changes direction.
2. Find the total distance travelled by particle X in the first 3.5 seconds.
Another particle, Y , moves along the same line, starting at the same time as particle X . The velocity of particle Y is given by $v_{\mathrm{Y}}=5-t, 0 \leq t \leq 30$ .
3. a. Given that particle X and Y start at the same point, find the displacement function $s_{\mathrm{Y}}$ for particle Y .
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b. Find the other value of t when particles X and Y meet.