I want to make a parametric plot using pgfplot in LaTex. My equations are
\rho= K (sinh t-t)
P= 1/3 K (sinh t - 8 sinh (1/2) t +3t) with K=1\4pi

I have written the LaTex code for equations , now please help me plot the graph
\usepackage[a4paper, total={6in, 8in}]{geometry}

\underline{Chandrashekhar EOS (1935)} : \\
\overline\rho&= K ~\Big(\sinh ~t ~- ~t\Big)\\
\overline P &=\frac{1}{3} K ~ \Big(\sinh~t -~ 8~ \sinh\frac{1}{2} t +~ 3t\Big)\\