Làm ra luôn nhaCâu trả lời: Làm ra luôn nha

\(\left(x-1\right)\left(y-4\right)+\left(4-y\right)^2\)\(=-\left(x-1\right)\left(4-y\right)+\left(4-y\right)^2\)\(=\left(4-y\right)\left[-x+1+4-y\right]\)\(=\left(4-y\right)\left(-x+5-y\right)\)\(=\left(y-4\right)\left(x+y-5\right)\)Câu trả lời: \(\left(x-1\right)\left(y-4\right)+\left(4-y\right)^2\)\(=-\left(x-1\right)\left(4-y\right)+\left(4-y\right)^2\)\(=\left(4-y\right)\left[-x+1+4-y\right]\)\(=\left(4-y\right)\left(-x+5-y\right)\)\(=\left(y-4\right)\left(x+y-5\right)\)