Exact versus numerical results:
{{{id=0| 19/7 /// }}} {{{id=30| 187/423 + 171/347 /// }}} {{{id=1| n(19/7, 300) /// }}} {{{id=2| pi /// }}} {{{id=5| n(pi, 300) /// }}}Really big numbers are no problem for Sage:
{{{id=6| factorial(400) /// }}}Symbolic work is easy for Sage:
{{{id=23| f(x)=sin(x^2) f.diff() /// }}} {{{id=25| integrate(sin(x)^2, x) /// }}}Plotting is impressive, too
{{{id=7| plot(20*sin(40/x), (x, -2, 2)) /// }}} {{{id=11| var('x y') plot3d(sin(x)*cos(y), (x, -3*pi, 3*pi), (y, -3*pi, 3*pi)) /// }}} {{{id=20| var('x') @interact def plot_example(f=sin(x^2),r=range_slider(-5,5,step_size=1/4,default=(-3,3)), thickness=(3,(1..10)), adaptive_recursion=(5,(0..10)), adaptive_tolerance=(0.01,(0.001,1)), plot_points=(20,(1..100)), linestyle=['-','--','-.',':'], gridlines=False, fill=False, frame=False, axes=True, c=Color('blue') ): show(plot(f, (x,r[0],r[1]), color=c, thickness=thickness, adaptive_recursion=adaptive_recursion, adaptive_tolerance=adaptive_tolerance, plot_points=plot_points, linestyle=linestyle, fill=fill if fill else None), gridlines=gridlines, frame=frame, axes=axes) /// }}}Sage does algebra: "regular," linear, abstract
{{{id=13| var('a b') expand((a+b)^3) /// }}} {{{id=12| solve(x^3-5*x^2+6, x) /// }}} {{{id=14| a = random_matrix(ZZ, 200, 200, x=10) /// }}} {{{id=16| a[34, 17] /// }}} {{{id=17| a.determinant() /// }}} {{{id=18| g = CyclicPermutationGroup(6) /// }}} {{{id=19| factor(factorial(20)) /// }}} {{{id=29| /// }}}