`A = (3x + 7)(2x + 3) - (3x - 5)(2x + 11)`
`= (6x ^ 2 + 9x + 14x + 21) - (6x ^ 2 + 33x - 10x - 55)`
`= 6x ^ 2 + 23x + 21 - 6x ^ 2 - 23x + 55`
`=76`
``
`B = (x ^ 2 - 2)(x ^ 2 + x - 1) - x(x ^ 3 + x ^ 2 - 3x - 2) `
`= (x ^ 4 + x ^ 3 - x ^ 2 - 2x ^ 2 - 2x + 2) - (x ^ 4 + x ^ 3 - 3x ^ 2 - 2x) `
`= (x ^ 4 + x ^ 3 - 3x ^ 2 - 2x + 2) - (x ^ 4 + x ^ 3 - 3x ^ 2 - 2x)`
`= (x ^ 4 + x ^ 3 - 3x ^ 2 - 2x) + 2 - (x ^ 4 + x ^ 3 - 3x ^ 2 - 2x)`
`= 2`
\(A=\left(3x+7\right)\left(2x+3\right)-\left(3x-5\right)\left(2x+11\right)\)
\(=\left(6x^2+9x+14x+21\right)-\left(6x^2+33x-10x-55\right)\)
\(=6x^2+23x+21-6x^2-23x+55\)
\(=76\) (ko phụ thuộc x)
\(B=\left(x^2-2\right)\left(x^2+x-1\right)-x\left(x^3+x^2-3x-2\right)\)
\(=\left(x^4+x^3-x^2-2x^2-2x+2\right)-\left(x^4+x^3-3x^2-2x\right)\)
\(=\left(x^4+x^3-3x^2-2x+2\right)-\left(x^4+x^3-3x^2-2x\right)\)
\(=\left(x^4+x^3-3x^2-2x\right)+2-\left(x^4+x^3-3x^2-2x\right)\)
\(=2\)