In uniform motion, So, from 1^st equation of motion are,
v=u + at

If a=0 then

v=u+0 x t

v = u + 0

or v = u

i.e. initial velocity is equal to the final velocity. Or the velocity is uniform.

From 2^nd equation of motion, s=ut+1/2at²

(if a=0)

s=ut+x 0 x t²

s = ut + 0

s = ut

From 3^rd equation of motion,

v² - u² = 2as

(if a=0)

v² - u² = 2 x 0 x s

v² - u²= 0

or v² = u²

Thus, the equations of motion with uniform velocity are:

1) v = u

2) s = ut

3) v² = u²