149.

plot[{2x-x^2,-x},[x,-1,4]]

plot x^2/3^2+y^2/2^2=1

plot y^2 = x^2(2^2-x^2)

plot (x^2+y^2)^2=2^2(x^2-y^2)

150. 

plot x^2/1^2+y^2/2^2+z^2/3^2=1

151.

parametricplot3d[{u,cos v *sin u, sin v * sin u},[u,0,pi],[v,0,2*pi]]

parametricplot3d[{u,cos v *e^(-u), sin v *e^(-u)},[u,0,2],[v,0,2*pi]]

parametricplot3d[{u,cos v *2*cosh(u/2), sin v *2*cosh(u/2)},[u,-2,2],[v,0,2*pi]]

parametricplot3d[{u,cos v *sqrt(u^2-3^2), sin v *2*sqrt(u^2-3^2)},[u,3,6],[v,0,2*pi]]

x^2-y^2=3^2

153.

plot[{2/3*x^(3/2)},[x,0,3]]

plot[{ln(cos x)},[x,0,pi/2]]

plot[{arcsin(e^(-x))},[x,0,1]]

154.

parametricplot[{2(u-sin u),2(1-cos u)},[u,0,2*pi]]

parametricplot[{2*cos^3u,2*sin^3u},[u,0,2*pi]]

polarplot[{2*u},[u,0,6*pi]]

polarplot[{2*(1+cos u)},[u,0,2*pi]]








parametricplot[{2(2cos u -cos (2u)),2(2sin u -sin (2u))},[u,0,2*pi]]