I should have mentionned it, but I rather think about it first.(adsbygoogle = window.adsbygoogle || []).push({});

Suppose f:A->B and g:B->C

then g*f:A->C

That makes sense.

Then they talked about f*g!

Is this possible? Think about it. If f has domain A, and g has range C, than how can f(x) equal anything, since the range of C is not equal to set A, which is what we need to calculate f.

f*g:B->?

I hope you understand.

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# Something brought up in class.

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