A = \frac{ρ S H}{2} (\frac{3 g H}{4} + \frac{1}{2} {(\frac{S H}{2 π R^{2} t})}^{2})

${A = \frac{\rho SH}{2}\left(\frac{3gH}{4}+\frac{1}{2}\left(\frac{SH}{2\pi R^2t}\right)^2\right)}$

Error