diff --git a/education/physics/PHYS2210/Unit 1.md b/education/physics/PHYS2210/Unit 1.md
index 51a705f..4d7d1a8 100644
--- a/education/physics/PHYS2210/Unit 1.md	
+++ b/education/physics/PHYS2210/Unit 1.md	
@@ -1,4 +1,4 @@
-Motion in a straight line is one dimensionial.
+Motion in a straight line is one dimensional.
 
 Kinematics or the physics of motion has 4 noteworthy parameters: time ($t$), position ($x$), velocity ($v$), and acceleration ($a$). 
 
@@ -14,3 +14,7 @@ Average velocity over a time interval $\Delta t$ is defined to be: **the displac
 
 $$ \bar{v} = \dfrac{\text{final position-initial position}}{\text{final time - initial time}} = \dfrac{x_2 - x_1}{t_2 - t_1} = \dfrac{\Delta x}{\Delta t}$$
 **Speed (m/s)** is defined to be the total distance traveled divided by the time taken. Speed and velocity are *not the same*. 
+
+
+$$ v_{\text{instant}} = v = \lim_{\Delta t \to 0}\frac{\Delta x}{\Delta t} = \frac{dx}{dt}$$
+- $x(t)$ -> position as a function of time
\ No newline at end of file