Function Grapher has the ability of creating tangent line and normal line of 2D curve. The following figure shows five tangent lines and five normal lines on the graph of equation y=sin(x).

The calculating results are shown in Result Editor

    Function y=sin(x)
        Tangent position: x=-2, y=-.9092974
            Slope: -.4161468
        Tangent position: x=-1, y=-.841471
           Slope: .5403023
        Tangent position: x=0, y=0
            Slope: 1
        Tangent position: x=1.57, y=.9999997
            Slope: 7.962743E-04
        Tangent position: x=3, y=.14112
            Slope: -.9899925

        Normal position: x=-2, y=-.9092974
            Slope: 2.402998
        Normal position: x=-1, y=-.841471
            Slope: -1.850816
        Normal position: x=0, y=0
            Slope: -1
        Normal position: x=1.57, y=.9999997
            Slope: -1255.849
        Normal position: x=3, y=.14112
            Slope: 1.010109

Graphing Calculator -> Function Grapher -> Tangent And Normal