For one, you left out a multiplication operator (*) in ‘eq2’. The numeric output is appropriate, since you’re identifying ‘Z0’ and ‘gamma’.
The code (corrected):
syms z g;
eq1=z*sinh(790*g)==(12.3+1i*1.49E-3);
eq2=tanh(395*g)==z*(1.8E-9);
[z,g] = solve(eq1,eq2,z,g)
produces:
z =
58452.259506186817111402883076281 + 3.5404010317307016714429740047407i
g =
0.00000026636472784652195740050195875373 + 0.000000000016133473234585554676003727620685i
Use the vpa or vpasolve functions if you don’t want quite so many digits.
