\(\left(3x-2\right)\left(5x+4\right)-\left(2x+7\right)\left(4x-1\right)+1\)
\(=15x^2+2x-8-8x^2-26x+7+1=7x^2-24x\)
(3x-2)(5x+4) - (2x+7)(4x-1)+1
= 15x2 + 12x - 10x - 8 - (8x2 - 2x + 28x - 7) +1
= 15x2 + 12x - 10x -8 - 8x2 + 2x - 28x + 7 +1
=(15x2 - 8x2) + (12x - 10x + 2x - 28x) - (8 -7-1)
= 7x2 - 24x
hello bạn của tôi
\(\left(3x-2\right)\left(5x+4\right)-\left(2x+7\right)\left(4x-1\right)+1\)
\(=15x^2+12x-10x-8-8x^2+2x-28x+7+1\)
\(=7x^2-24x\)
