Cool math trick i learned [Determinants]

[DrTacoElf]

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If you have 3 points in a coordinate system and you need to find the area of the triangle formed by them you can use the determinant of a 3 x 3 matrix.

Sarrus's Rule

Column 1 = x coordinates
Column 2 = y coordinates
Column 3 = all 1's

a b c
d e f
g h i

Area = (1/2) aei+bfg+cdh-ceg-bdi-afh
You will get a negative number but just disregard the Negative sign 🙂

Enjoy all the time you save with this trick 👍

 

[Biogirl361]

i don't know about all that, but i do know i wish ya good luck on the dat tomorrow!! 😀

 

[DrTacoElf]

i don't know about all that, but i do know i wish ya good luck on the dat tomorrow!! 😀

Thanks! i'm going over gen chem at the moment then PAT until about 1030pm and then bedtime 😎

 

[Blackstars]

Taco,

Good luck tommorrow, I'm sure you're to fine.

 

[rocknightmare]

umm hwo on earth did you memorize the formula??

 

[DrTacoElf]

umm hwo on earth did you memorize the formula??

Its really not that bad if you draw out the metrice. Its a symmetrical pattern which repeats itself.

 

[rocknightmare]

i will try to comit to memory.. are you sure that the labels are correct?

 

[DrTacoElf]

very sure, use a test problem to verify.

 

[sinned]

how does that system work, seems more complicating...

I see...you just gotta know the trivial relationship

 

[Sher9mm]

Well how did yo do, DrTacoElf?