ShmoopTube

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Sorry And here's your shmoop du jour brought to you

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by ducks more and more of them these days Or

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stopping to make sure the bread crumbs thrown to them

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are gluten free You know that which of the following

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is equivalent to the quantity x minus seven times quantity

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three x plus six times the quantity x squared minus

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four x minus five and hear the bench lands Well

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looks like solve this one We're gonna have tio consume

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mass quantities Cone heads know the pointy headed close with

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Yeah like we're old Well let's just take a look

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at the first two parts and princes and multiply those

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together For starters we can worry about the third one

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in a bit We're gonna multiply through x minus seven

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and three Acts plus 6 so we get three x

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squared plus six x minus twenty one x minus forty

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two Combine our ex terms and that's improvised three x

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squared minus fifteen x minus forty two All right now

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we'll introduce that last part back into our lives Like

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you never left this one's a bit more complex but

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it follows the same general principle we need to take

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The first term in the first polynomial multiply it by

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the first term in the second polynomial then do the

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same for the second third terms Then we go back

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to the first polynomial and lather intra pete with the

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second term there And finally with third once we're done

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we should have a string of terms about a half

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mile long but at least we'll be getting somewhere alright

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Well three x squared times x squared is three acts

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to the fore Three x squared times negative for axes

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negative twelve x cube and three x squared times Negative

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five is negative fifteen x square All right back to

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the first polynomial middle term now banking fifty Next time's

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expert is negative fifty next cube negative fifty next times

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negative for exes positive sixty x squared and negative fifteen

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x times negative five is positive Seventy five acts are

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home stretch first pollen on the old third term hanging

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a forty two times x squared is negative Forty two

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x squared Thank you forty two times negative four axes

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sixty eight x and negative forty two times five his

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positive to ten and we're done florida now to combine

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Like terms wherever possible we need to get our ducks

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in a row as it is there flapping all over

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have only got one accident fourth term so we can

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leave him along Negative twelve x cubed minus fifteen x

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cube is negative twenty seven x q taking fifteen x

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squared plus sixty x squared minus forty two x squared

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is three x squared Seventy five Acts plus 168 axes

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two hundred forty three acts And then finally we can

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tack on the two hundred ten At the end there

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are all together Now We have to react to the

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fourth one twenty seven execute plus three x squared plus

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two hundred forty three x plus two ten it's option

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b There's got to be careful with all those positive

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and negative signs but as long as you keep straight

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problems like this one as bad as they first appear

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Although tried telling these guys they can barely stand right 00:02:55.671 --> [endTime] frank

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