ZGrapher

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This graphing calculator can plot y(x), x(y), polar, parametric and table-defined functions. All your graphs and coordinate space may be fully customized. You can comment your graphs using labels and legend. For a few seconds you can obtain derivatives, tangents, normals and calculate integrals. Regression analysis will help you to find trend of your data. Results of your work may be exported to Word or saved as BMP, GIF and PCX pictures.