#postscript("../../WriteUp/Graphics/Chapter2/chap_2_sect_5_prob_26_plot.eps", onefile=FALSE, horizontal=FALSE)

as = seq( 0, 10, length.out=100 )

plot( as, -sqrt(as), xlim=c(-max(as), +max(as)), ylim=c(-sqrt(max(as)), +sqrt(max(as))), type='l', col='green', xlab='a', ylab='' )
lines( as, +sqrt(as), type='l', col='green' )
abline(h=0, col='black')
grid()

#dev.off()