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It's impressive that these expressions are able to stay so rational even when they're having operations performed on them.
Jack and Jill went up the hill to fetch a pail of water. But what happened when they got up there? They’ve been gone an awfully long time…
Adding and Subtracting Rational Expressions 1930 Views
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Description:
Don’t you hate it when you have too many rational expressions—or too few? Thank goodness for addition and subtraction. We don’t know what we’d do without those two.
Transcript
- 00:03
Adding and Subtracting Rational Expressions a la Shmoop
- 00:07
Scientists finally discovered that the duck-billed platypus is actually the result of an alien [Platypus being sucked into a UFO]
- 00:12
DNA-splicing experiment.
- 00:14
Let's help them to unsplice the duck out of the platypus and see what the heck it originally [Scientists with the platypus on an operating table]
- 00:18
was.
Full Transcript
- 00:19
Of course, we're going to have to simplify things...
- 00:22
We'll be representing the unsplicing with the following equation...
- 00:25
Five x over x plus three minus x minus three over x plus three.
- 00:33
Duck DNA is mathematically represented by x minus three over x plus three. [Duck and a platypus with a DNA helix spinning behind them]
- 00:39
Since they have a common denominator…
- 00:41
…we can just squish them together into five x minus x minus three in parentheses, all [Hands squish the equation together]
- 00:47
over x plus three.
- 00:50
Getting rid of the parentheses, this breaks down into five x minus x plus three all over [Parentheses looks upset]
- 00:56
x plus three.
- 00:57
So the answer is four x plus three over x plus three.
- 01:01
This happens to be the DNA code for that kid from the Sixth Sense. [Kid with a duck on his knee]
- 01:04
We always wondered what happened to him. [Duck lays an egg]
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It's impressive that these expressions are able to stay so rational even when they're having operations performed on them.
Jack and Jill went up the hill to fetch a pail of water. But what happened when they got up there? They’ve been gone an awfully long time…
