Precalculus Ma 112: Section 1.8 Completing the square #1

[Hashbrowniepie]

thank you sir!

[silencedidgood]

Love this and all you do. Camerawork could be a little less choppy...Think of the Seinfeld where Jerry takes over for Kramer and then they love Jerry's work.

[Unknown1101]

First of all, thanks a bunch for this very informative video, just what I was looking for. I have a question though...

I understood everything up until:

(x+3/2)²-9/4-4

then you suddenly made it to (x+3/2)²-9/4-16/4

why did you make -4 to -16/4?

[ProfessorElvisZap]

Because subsequently, I will have to add -9/4 and -4. To add fractions, one gets a common denominator. In the sequel, we will add -B^2/(4A) + C= (-B^2+4AC)/(4A).

[IlRockUrLife]

(-9/4)=-2,25  -2,25-4=-6,25 -> -25/4

[lamarjlp914]

(5/6)^2 = 25/36, you wrote 25/12

[ProfessorElvisZap]

3(25/36)=25/12 ---- you have to multiply through by the 3.

[lamarjlp914]

ohhhh I thought I missed something. Thanks

[CarbnXL]

duuuuuuuuude you some sorta super genius

[daky1952]

Thank you. I don't understand well English, but understand well you.Kiss

[bob963me]

Wonderful! I minored in Mathematics in college and no one ever told me the geometric basis for completing the square. You just cleared up 20 years of confusion for me.

[TheImpressionable]

@bob963me you should always ask why, don't just plug numbers into a formula. 

[hotshot101777]

cool. you look like al gore. :) good lesson,, just a little bit fast for me though. 5/5 :)

[PIGSYMAGICC]

Do I need to know this for GCSE Maths?

[Cheeeselets]

yes you do.

[map1k9]

no you dont

[afgsabour]

excellent video, very insightful in 10 mins and fun to watch.. I actually didn't know completing the square was tied in with the area of two rectangles, so that was cool.

the "blob" made me laugh, I'm guessing you teach physics as well, physicist have a hilarious sense of humor with their math.

[brengera]

i knew how to do all this, but i have never seen it truly done out and explained, so it was very helpful :)

[ProfessorElvisZap]

Yes. 10 minute time limit. Also, students should watch more than once and fill in any missing steps.

[Supahstah93]

cool. very helpful.