\(\left(a-b\right)^2-\left(b-a\right)\\ =\left(a-b\right)\left(a-b\right)+\left(a-b\right)\\ =\left(a-b\right)\left(a-b+1\right)\)
`HaNa☘D`
\(\left(a-b\right)^2-\left(b-a\right)\)
\(=\left(a-b\right)^2+\left(a-b\right)\)
\(=\left(a-b\right)\left(a-b+1\right)\)
(a-b)^2-(b-a)
=(a-b)^2+(a-b)
=(a-b)(a-b+1)