Solving Mistake in my Book: (b-a)^2/12

[montoyas7940]

(1/3)(b^2+ab+a^2)-(1/4)(b^2+2ab+a^2)

= (b-a)^2
--------
12


I am ok with this but there is am intermediate step shown


(b^2-2ab+a^2)
-------------- (2)
12

I don't see where the multiplication by 2 comes from and it is not shown in the errata.

 

[kdv]

(1/3)(b^2+ab+a^2)-(1/4)(b^2+2ab+a^2)

= (b-a)^2
--------
12


I am ok with this but there is am intermediate step shown


(b^2-2ab+a^2)
-------------- (2)
12

I don't see where the multiplication by 2 comes from and it is not shown in the errata.

You are right that there should be no multiplication by two there.

I am not sure how it exactly appears in your book, but does it appear like you typed it here, with the 2 between parentheses? I am asking because sometimes books number equations and often when equations are numbered, the number is put between parentheses.

 

[scarecrow]

 

[montoyas7940]

It is clearly a multiplication. It is a solution manual for a text and I can't find a published errata. I am just going to assume it is a mistake and move on. Thank you, kdv.

 

[kdv]

It is clearly a multiplication. It is a solution manual for a text and I can't find a published errata. I am just going to assume it is a mistake and move on. Thank you, kdv.

Ok. Then it is a typo.

You are welcome.