Explanation:
x = 3.00
– 2.00t + 3.00,
Distance of object at 2 second,
x (t=2) = 3(4) - 2(2) +3
x (t=2) = 12-4 +3
x (t=2) = 11 m
Distance of object at 3 second,
x (t=3) = 3(9) - 2(3) +3
x (t=2) = 27 - 6 + 3
x (t=2) = 24 m
a) the average speed between t = 2.00 s and t = 3.00 s,
Average speed = ![\frac{Total distance}{ Total time}](https://tex.z-dn.net/?f=%5Cfrac%7BTotal%20distance%7D%7B%20Total%20time%7D)
Average speed = ![\frac{x (t=2) + x (t=3)}{3}](https://tex.z-dn.net/?f=%5Cfrac%7Bx%20%28t%3D2%29%20%2B%20x%20%28t%3D3%29%7D%7B3%7D)
Average speed = ![\frac{24+11}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B24%2B11%7D%7B3%7D)
Average speed = ![\frac{35}{3}](https://tex.z-dn.net/?f=%5Cfrac%7B35%7D%7B3%7D)
Average speed = 11.66 ![\frac{m}{s}](https://tex.z-dn.net/?f=%5Cfrac%7Bm%7D%7Bs%7D)
b) the instantaneous speed at t = 2.00 s and t = 3.00 s,
Instantaneous speed = ![\frac{dx}{dt}](https://tex.z-dn.net/?f=%5Cfrac%7Bdx%7D%7Bdt%7D)
Instantaneous speed(v) = 6t - 2![\left \{ {{t=2} \atop {t=3}} \right.](https://tex.z-dn.net/?f=%5Cleft%20%5C%7B%20%7B%7Bt%3D2%7D%20%5Catop%20%7Bt%3D3%7D%7D%20%5Cright.)
Instantaneous speed,v(t=2 to t=3) = 18-2-12+2
Instantaneous speed, v = 6 ![\frac{m}{s}](https://tex.z-dn.net/?f=%5Cfrac%7Bm%7D%7Bs%7D)
c) the average acceleration between t = 2.00 s and t = 3.00 s
average acceleration = ![\frac{average velocity}{time}](https://tex.z-dn.net/?f=%5Cfrac%7Baverage%20velocity%7D%7Btime%7D)
average acceleration = ![\frac{11.66}{3-2}](https://tex.z-dn.net/?f=%5Cfrac%7B11.66%7D%7B3-2%7D)
average acceleration = 11.66 ![\frac{m}{s^{2} }](https://tex.z-dn.net/?f=%5Cfrac%7Bm%7D%7Bs%5E%7B2%7D%20%7D)
d) the instantaneous acceleration at t = 2.00 s and t = 3.00 s
instantaneous acceleration = ![\frac{dv}{dt}](https://tex.z-dn.net/?f=%5Cfrac%7Bdv%7D%7Bdt%7D)
instantaneous acceleration =6
instantaneous acceleration = 6 ![\frac{m}{s^{2} }](https://tex.z-dn.net/?f=%5Cfrac%7Bm%7D%7Bs%5E%7B2%7D%20%7D)
e) for x =0
0 = 3.00
– 2.00t + 3.00
a = 3, b=-2, c=3
t= ![\frac{-b \pm \sqrt{b^{2} - 4ac} }{2a}](https://tex.z-dn.net/?f=%5Cfrac%7B-b%20%5Cpm%20%5Csqrt%7Bb%5E%7B2%7D%20-%204ac%7D%20%7D%7B2a%7D)
t= ![\frac{2 \pm \sqrt{4 - 36} }{6}](https://tex.z-dn.net/?f=%5Cfrac%7B2%20%5Cpm%20%5Csqrt%7B4%20-%2036%7D%20%7D%7B6%7D)
t= ![\frac{2 \pm \sqrt{-32} }{6}](https://tex.z-dn.net/?f=%5Cfrac%7B2%20%5Cpm%20%5Csqrt%7B-32%7D%20%7D%7B6%7D)
general solution of this equation gives imaginary value. Hence, the given object is not at rest.