# Mechanics/Calculus question phrasing help

## Homework Statement

Derive the kinematic equations for constant a from change in x=V(avg)Xt & change in v= a(avg)Xt

## Homework Equations

v=v(o)+at
(Every other equation that can be made from x=x(1)+V(0)t+.5at^2)
x= position
a=acceleration (constant)
v=velocity
t=time

## The Attempt at a Solution

My main problem with this problem is that I don't know exactly what it's asking and the phrasing confuses me.
But what I did was turned the change in x=V(avg)Xt into v=v(o)+at through deriving and substitution.
For the change in v= a(avg)Xt equation, I turned it into a=change in v/t through deriving and substitution.
Once again I'm not even sure that I even answered the question, can someone please interpret the question in a way I can understand it?

hi max

since the acceleration is constant, $$\inline{a_{avg}=constant=a}$$
and the equations you are supposed to use are $$\inline{x=V_{avg}t}$$ and
$$\text{change in v}=a_{avg}t=at$$

now remember that

$$V_{avg}=\frac{V+V_o}{2}$$

and change in V=final velocity - initial velocity = $V-V_o$

so use these equations , manipulate them....

for example... $\text{change in v}=V-V_o = at$
so $V=V_o +at$ this would be one of the equations of kinematics for the constant
acceleration..

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Hi issac, I know how to manipulate the equations and such, my main problem is that I don't know what the question itself is asking. Like am I supposed to find a= through the 2 equations?

there are 3 main equations of the kinematics for the constant acceleration ..... i already showed you one of them....now to get the second equation, you need to eliminate V and get an equation in x, V_o ,a and t...... do it