This is to do with mechanics, which as far as I know is pre-calc, not pre-algebra.
Question: A particle has an initial velocity of and is accelerating in the direction . If the magnitude of the acceleration is , find the velocity vector and the speed of the particle after 2 seconds.
Answer:
velocity vector:
speed of particle:
I am literally stumped on how to achieve this answer. If you can tell me what to do to get there, I will try working it out .
Ehh, that seems too condensed. Can you expand on the v(t) and v(2) parts, and is there a way without using arctan? We haven't had to use trigonometry for these questions, although we have used pythagoras ( ).
I worked out the 5i and 5j components somehow, but that's as far as I got.
you should know that forms a 45-45-90 triangle, so there is no need for the arctangent function in this case.
the basic velocity kinematics equation for constant acceleration is
component-wise, for your problem, that would be
so, velocity as a function of time in the x-direction is
and, velocity as a function of time in the y-direction is
the overall velocity vector represented in component form is
that's about as easy as I can put it for you without teaching about two-dimensional kinematics in total.