Write the equation for a harmonic wave with amplitude $2.50 \mathrm{cm}$ and angular frequency $2.90 \mathrm{rad} / \mathrm{s}$ that is moving in the $+x$ -direction with a wave speed that is 5.00 times as fast as the maximum transverse speed of a point on the string. At $t=0,$ the point $x=0$ is at $y=0$ and is moving in the $-y$ -direction.