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# Fraction over a fraction... watch

1. I'm churning through this answer paper, and I found a small step which I don't quite understand! D:

Where in the world did the one on the top go? Why did they switch place?
Thanks in advance! I may just be missing something obvious
2. (Original post by MarcusThePotato)
I'm churning through this answer paper, and I found a small step which I don't quite understand! D:

Where in the world did the one on the top go? Why did they switch place?
Thanks in advance! I may just be missing something obvious
If you think about the rule that any number or function over itself is 1 () then it stands that:

What you can do here is set which means you multiply the numerator and denominator by . This means you end up with on the top and on the bottom!
3. I always imagine it like this. You have a fraction:

Multiply it by b/b (i.e. 1)

When multiplying fractions you multiply both the top and bottom, so it becomes:

so

Now, b/b is 1, so that cancels out:

So,
4. bless both of you!

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