Question

Phân tích thành nhân tử : ( 4 - x )² + ( x - 4 )( x - 5 ) - 4( x - 5 )² + 1

Mình cần gấp lắm ! Mong mọi người giúp đỡ !

Answer 1

\(\left(4-x\right)^2+\left(x-4\right)\left(x-5\right)-4\left(x-5\right)^2+1\)

= \(16-4x+x^2+x^2-5x-4x+20-4\left(x^2-5x+25\right)+1\)

= \(37-13x+2x^2-4x^2+20x+100\)

= \(137+7x-2x^2\)

Answer 2

\(=\left(x-4\right)^2+\left(x-4\right)\left(x-5\right)-\left(2\left(x-5\right)\right)^2+1\)

\(=\left(x-4\right)\left(2x-9\right)-\left(\left(2x-10\right)^2-1\right)\)

\(=\left(x-4\right)\left(2x-9\right)-\left(2x-11\right)\left(2x-9\right)\)

\(=\left(2x-9\right)\left(x-4-2x+11\right)=\left(2x-9\right)\left(7-x\right)\)