Laplace Transform of unit step

f(t)={ sint if 0<= t < 2pi / 0 else

Answer 1

[Walter Roberson]

hint: sympref 'heavisidestorigin'

then you can code the piecewise definition in terms of heaviside() and follow with laplace()

Answer 2

[Koay Xuan Hong]

Answer 3

[VBBV]

syms t
iwant = piecewise(0<t<2*pi,sin(t),0);
L = laplace(heaviside(iwant));
fplot(L,[-2*pi 2*pi])

Try like this , and also use heaviside step function as @Walter Roberson suggested

[VBBV]

syms t
iwant = piecewise(0<t<2*pi,sin(t),0);
fplot(iwant,[-2*pi 2*pi])