# KmPlot/Using Sliders

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A main feature of KmPlot is to visualize the influence of parameters to the curve of a function.

## Moving a Sinus Curve

Let's see, how to move a sinus curve left and right:

• Create a new Cartesian plot.
• Enter the equation
`f(x,a) = sin(x-a)`
• Check the Slider option and choose Slider No. 1 from the drop down list.
• To make the available sliders visible, check View -> Show Sliders

Now you can move the slider and see how the parameter value modifies the position of the curve.

## Trajectory of a Projectile

Now let's have a look at the maximum distance of a projectile thrown with different angles. We use a parametric plot depending on an additional parameter which is the angle.

• Define a constant v_0 for the starting velocity.
• Create a new parametric plot
• Enter the equations
```f_x(t,α) = v_0∙cos(α)∙t
f_y(t,α) = 2+v_0∙sin(α)∙t−5∙t^2```
• Check the Slider option and choose Slider No. 1 from the drop down list.
• To make the available sliders visible, check View -> Show Sliders

Now you can move the slider and see how the distance depends on the parameter value.