The rectilinear motion of the body is described by the equation x = 6 + 8t – 2t2.
The rectilinear motion of the body is described by the equation x = 6 + 8t – 2t2. Find the path covered by the body in 3 seconds of movement.
If a rectilinear body is described by a quadratic equation in time, then this is uniformly accelerated motion. Since the free term of the equation is not zero, the motion began from a point equal to the free term (projection onto the x axis). The time is set in seconds, so the distance is in meters.
So, the movement at the moment t = 0 began from the point 6m:
x = 6 + 8 * 0 – 2 * t ^ 2.
3 seconds have passed, by this moment the body is at the point x1:
x1 = 6 + 8 * 3 – 2 * 3 ^ 2;
x1 = 6 + 24 – 2 * 9;
x1 = 30 – 18;
x1 = 12.
The starting point from which the movement began is 6m, which means that the body has passed 6 meters in 3 seconds.
Answer: in 3 seconds, the body has traveled 6 meters.