How to | Change the Form of Input and Output

The user interface for the Wolfram System provides many options for formatting input and output.

The sum of from to is :

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Out[1]=

While correct, this does not look like traditional mathematics. Select the cell group, then choose the menu item Cell Convert To TraditionalForm:

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Out[2]=

Alternatively, if you only want to format the answer, apply TraditionalForm:

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Out[3]//TraditionalForm=
    

InputForm and StandardForm work in reverse.

Use InputForm to find out how to type an expression into the Wolfram Language:

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Out[1]//InputForm=

StandardForm is more compact than InputForm and is unambiguous to the Wolfram Language:

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Out[2]//StandardForm=

TraditionalForm is sometimes ambiguous; in this case, the Wolfram Language treats first as a number and then as a function:

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Out[3]//StandardForm=