What does the delta symbol represent in the equation?

change in velocity

magnitude of velocity

distance of velocity

khange in velokity

Whenever you see the delta symbol infront of another, it always represents change. In other words:

Δu = u_f - u_i

u_i means "initial velocity" u_f means "final velocity"

And in general, ΔX means Xfinal - Xinitial