> #HW5b 11.6\
with(plots):
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> #1\
implicitplot3d(x^2-y^2+z^2-1,x=-3..3,y=-3..3,z=-3..3);
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> #5\
implicitplot3d(4*z^2-x^2-y^2-1,x=-3..3,y=-3..3,z=-3..3);
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> #9\
implicitplot3d(y^2-x^2-z^2,x=-3..3,y=-3..3,z=-3..3);
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> #13\
implicitplot3d(y^2+9*z^2-9,x=-3..3,y=-3..3,z=-3..3);
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>