import geometry; size(12cm,0); currentcoordsys=cartesiansystem((1.25,0.75),i=(1,0.5),j=(-1,1)); coordsys Rp=currentcoordsys; coordsys R=defaultcoordsys; show(Label("$O$",align=SE), "$\vec{\imath}$", Label("$\vec{\jmath}$",align=E), R); show("$O'$", "$\vec{u}$", "$\vec{v}$", Rp, xpen=invisible); vector w=(0.25,0.5); point P=(1,0.5); dot("$P$",P,W); show("$\overrightarrow{w}$", w); /**/ point Pp=rotateO(90)*P; dot("Pp=rotateO(90)*P", Pp, W); dot("rotate(90,Pp)*P", rotate(90,Pp)*P, W); /**/ dot("scale(-2,Pp)*P", scale(-2,Pp)*P, NE); /**/ dot("scaleO(2)*P", scaleO(2)*P,red); /**/ dot("xscaleO(2)*P", xscaleO(2)*P); /**/ dot("yscaleO(2)*P", yscaleO(2)*P,W); vector wp=rotateO(90)*w; show("$\overrightarrow{w'}$", wp); draw("$\overrightarrow{w}$", (0,0)--locate(w), W, Arrow); draw("$\overrightarrow{w'}$", (0,0)--locate(wp), S, Arrow);