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Chalkboard Math



#6

The recent thread about the chalkboard math from the movie "The Day the Earth Stood Still" reminded me of a photo from the current Discover magazine (July/August) advertising a calculus course. I asked my son (recent AP calc student) what was wrong in this picture. Took him about 5 seconds to see the omission. Not that I'm perfect on a chalkboard (or white board) either, but it's a fun past-time to spot these things. Any others out there?

CHUCK


#7

I believe the middle formula should be

#8

Quote:
"I asked my son (recent AP calc student) what was wrong in this picture. Took him about 5 seconds to see the omission. Not that I'm perfect on a chalkboard (or white board) either, but it's a fun past-time to spot these things"

The derivation looked fine, assuming that the function was f(x) = x2. Was it the missing hash mark from the second "f(x)"?

-- KS

Edited: 10 June 2010, 1:23 a.m.


#9

Quote:
Was it the missing hash mark from the second "f(x)"?
I´d have mentioned the same thing... mostly because the thread refers to an omission. The second line of the derivative evaluation should start with
f'(x)=
instead of
f(x)=

Luiz (Brazil)


Edited: 10 June 2010, 7:51 a.m.


#10

FWIW, I concur d:-)


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