Question

derive s=ut+1/2at2 plz......................... ans soon

Answer 1

For deriving the equation of motion for a uniformly accelerated  body with respect to velocity.
a=dv/dt 
dv=a*dt
$\int\limits^u_v \, dv= \int\limits^0_t {a} \, dt$
v-u=at
v=u+at(1st equation of motion)
The velocity of body is given by first derivative.
v=ds/dt
ds=v dt
v=u+at , ds=(u+at)dt
differentiating the above equation.
$\int\limits^0_s \, ds= \int\limits^0_t {u} \, dt+ \int\limits^0_t {at} \, dt$
s=ut+1/2 at^2