\magnification=\magstep1

$$
x(t) \quad = \quad A \thinspace \sin(kx)
$$

$$
v(t) \quad = \quad {{dx}\over{dt}} \quad = \quad kA \thinspace \cos(kx)
$$

$$
a(t) \quad = \quad {{dv}\over{dt}} \quad = \quad -k^2 A \thinspace \sin(kx)
$$




\bye
