$\"\"$

Statement :The sum of two increasing functions is increasing.

Let the two increasing functions are $\"\"$ and $\"\"$ .

Sum of the two increasing functions is $\"\"$ .

Apply derivative on each side.

$\"\"$

For the above increasing functions $\"\"$ and $\"\"$ .

So $\"\"$ .

$\"\"$

Therefore sum of two increasing functions is increasing.

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True.