Question $3$:

Example $6\mathrm{.}6$ only plot in Matlab, given equation of $V$

Consider the trough shown in the figure, it is found that the solution of $V$ at any point in the trough is as follows:

$V(x,y)=10sin(\frac{3x}{b})\frac{sinh(\frac{3y}{b})}{sinh(\frac{3a}{b})}$

Plot the graph of V using Matlab, take $a=5$ and $b=5$ Show the full code and screenshot of the plot.