2 one typo and some minor formatting

When doing a RegionPlot andRegionPlotand then exporting (or saving from the front end) as PDF or EPS, there are small whilewhite lines in the filling of the region. Here's an example created with RegionPlot[x^2+y^2<1,{x,-1,1},{y,-1,1},PlotStyle->Black]:

Is there any way to prevent those white lines while keeping it vector graphics? Note that those lines do not appear on screen, only in the exported file.

Also note that my actual graphics is more complex and especially has several different-coloured regions.

When doing a RegionPlot and then exporting (or saving from the front end) as PDF or EPS, there are small while lines in the filling of the region. Here's an example created with RegionPlot[x^2+y^2<1,{x,-1,1},{y,-1,1},PlotStyle->Black]:

Is there any way to prevent those white lines while keeping it vector graphics? Note that those lines do not appear on screen, only in the exported file.

Also note that my actual graphics is more complex and especially has several different-coloured regions.

When doing a RegionPlotand then exporting (or saving from the front end) as PDF or EPS, there are small white lines in the filling of the region. Here's an example created with RegionPlot[x^2+y^2<1,{x,-1,1},{y,-1,1},PlotStyle->Black]:

Is there any way to prevent those white lines while keeping it vector graphics? Note that those lines do not appear on screen, only in the exported file.

Also note that my actual graphics is more complex and especially has several different-coloured regions.

When doing a RegionPlot and then exporting (or saving from the front end) as PDF or EPS, there are small while lines in the filling of the region. Here's an example created with RegionPlot[x^2+y^2<1,{x,-1,1},{y,-1,1},PlotStyle->Black]: