So in my theoretical physics class my professor was reminding us ("reminding") of what "linear" means, such as a linear functions or a linear operator. He said the definition was:(adsbygoogle = window.adsbygoogle || []).push({});

1. f(ax) = a f(x)

2. f(x + y) = f(x) + f(y)

Functions or operators are "linear" if they meet the above 2 conditions.

I am confused because, if I take a line... y = mx + b, which I completely consider to be linear, it doesnt' match either of those conditions.

Are there 2 different kinds of linear, am I losing my mind... or what?

thanks

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# Linear functions/operators conflicting understanding

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