Câu 2:

\(A\left(x\right)=x^2+3x+1\)

\(B\left(x\right)=2x^2-2x-3\)

a) Tính A(x) là sao em?

b) \(A\left(x\right)+B\left(x\right)=\left(x^2+3x+1\right)+\left(2x^2-2x-3\right)\)

\(=x^2+3x+1+2x^2-2x-3\)

\(=\left(x^2+2x^2\right)+\left(3x-2x\right)+\left(1-3\right)\)

\(=3x^2+x-2\)

Câu 1:

\(M\left(x\right)=x^3+3x-2x-x^3+2\)

\(=\left(x^3-x^3\right)+\left(3x-2x\right)+2\)

\(=x+2\)

Bậc của M(x) là 1

Câu 3

a) \(3x\left(x^2-x+1\right)\)

\(=3x.x^2-3x.x+3x.1\)

\(=3x^3-3x^2+3x\)

b) \(\left(2x^2+x-1\right):\left(x+1\right)\)

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

\(=\left[\left(2x^2+2x\right)-\left(x+1\right)\right]:\left(x+1\right)\)

\(=\left[2x\left(x+1\right)-\left(x+1\right)\right]:\left(x+1\right)\)

\(=\left(x+1\right)\left(2x-1\right):\left(x+1\right)\)

\(=2x-1\)

cau 1 :1,6

câu 2 : sai đề bài

cau 3 chua lam duoc 

cau 4 : chua lam duoc

cau 5 :101/10

1) 2n - 5 \(⋮\)n + 1

    2(n + 1) - 7 \(⋮\)n + 1

Do 2(n+1) \(⋮\)n+1 nên 7 \(⋮\)n+1 \(\Rightarrow\)n + 1 \(\in\)Ư(7) = { 1; -1; 7; -7}

Với n + 1 = 1 \(\Rightarrow\)n = 0

     n + 1 = -1 \(\Rightarrow\)n = -2

     n + 1 = 7 \(\Rightarrow\)n = 6

     n + 1 = -7 \(\Rightarrow\)n = -8

Vậy n = { 0; -2; 6; -8}

1/\(\left(x^2-6x+15\right):\left(x-3\right)\)

Đặt cột dọc ta được x-3 dư 6 

2/a/\(p=\left(x+1\right)^3+\left(x+1\right)\left(6-x^2\right)-12\)

\(=x^3+3x^2+3x+1+6x-x^3+6-x^2-12\)

\(=2x^2+9x-11\)

b/thay x = -1/2 ta đc \(2.-\left(\frac{1}{2}\right)^2+9.-\frac{1}{2}-11\)

\(=\frac{1}{2}+\left(-\frac{9}{2}\right)-11\)

\(=\left(-15\right)\)

Câu 1:

\(A\left(x\right)+B\left(x\right)\)

\(=\left(6x-4x^3+x-1\right)+\left(-3x-2x^3-5x^2+x+2\right)\)

\(=\left(6x+-3x+x\right)-\left(4x^3+2x^3\right)-5x^2+\left(-1+2\right)\)

\(=-6x^3-5x^2+4x+1\)

\(A\left(x\right)-B\left(x\right)\)

\(=\left(6x-4x^3+x-1\right)-\left(-3x-2x^3-5x^2+x+2\right)\)

\(=\left(-4x^3+2x^3\right)+5x^2+\left(6x+x-x\right)+\left(-1-2\right)\)

\(=-2x^3+5x^2+6x-3\)

Câu 2:

12.(x-1)=0

x-1=0/12

x-1=0

x=1+0

x=1

các bn ơi có ai trường THCS Trần Quang Diệu ko ?

cảm ơn nha