comparing it with standard equation $y = 2A\sin \frac{{2\pi x}}{\lambda }\cos \frac{{2\pi x}}{\lambda }$
We have $\frac{{2\pi x}}{\lambda } = 2\pi x$ ==> $\lambda = 1m$
Minimum distance of string (first mode) ${L_{\min }}\, = \frac{\lambda }{2} = \frac{1}{2}m$
(Young's modulus of wire $Y =9 \times 10^{10}\, Nm ^{-2}$ ), (to the nearest integer),
Given, $F 1= F 2=500\, Hz$. speed of air $=330\, m / s$