5x 10 4x 8 nhân 4 2x x 2 July 8, 2019 16 32 64 128 (5x−10) 2 −9x 2 =(4x−5)(4x+5) 3) (5 - 2x)(4x ^ 2 + 10x + 25) =2 5x-8x^ 3 4) (6 - 5x)(36 + 30x + 25x ^ 2) = 108x - 125x ^ 3
