A guitar string of length L = 0.91 m is oriented along the x-direction and under a tension of T = 101 N. The string is made of steel which has a density of ρ = 7800 kg / m3. The radius of the string is r = 6.6 x 10-4 m. A transverse wave of amplitude A = 0.0020 m is formed on the string. Part (d) Assume a form y2 = A sin(α) for the transverse displacement of the string. Write an expression for α of a transverse wave on a string traveling along the negative x-direction in terms of its wavenumber k, the position x, its angular frequency ω, and the time t.