a: \(A\left(x\right)=x^2-3x-3x^2+6x+17\)

\(=-2x^2+3x+17\)

\(B\left(x\right)=3x^2-7x+3-3x^2+6x-12\)

\(=-x-9\)

b: \(A\left(x\right)+B\left(x\right)=-2x^2+3x+17-x-9=-2x^2+2x+8\)

c: \(A\left(x\right)-B\left(x\right)=-2x^2+3x+17+x+9=-2x^2+4x+26\)

a) M(x) + N(x) + P(x) = x⁵ + 7x⁴ - 6x³ - 3x² + x - 4

Đù mỗi mình sai :v

Miyuki Misaki đen lắm

nguyenthihuyentrang

( 2x  - 5)²  - ( 4x - 1 ) ( x + 3 ) = 5 

=> ( 2x ) ²   - 2 . 2x. 5 + 5² - 4x² + 12x - 3 - x = 5 

=> 4x²    - 20x + 15 - 4x²  + 11x - 3 = 5 

=> -20x + 11x = 5 + 3 - 15 

=> -9x = -7  =>  x = 7/9 

^^ Học tốt! 

M.n giup mk vs ak!! mk se tag k cho m.n, camon ah!

a)\(A\left(x\right)=5x^5-4x^4-2x^3+4x^2+3x+6\\ B\left(x\right)=x^5+2x^4-2x^3+3x^2-x+\frac{1}{4}\)

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

\(\left(5x^5-4x^4-2x^3+4x^2+3x+6\right)+\left(x^5+2x^4-2x^3+3x^2-x+\frac{1}{4}\right)\\ =5x^2-4x^4-2x^3+4x^2+3x+6+x^5+2x^4-2x^3+3x^2-x+\frac{1}{4}\\ =\left(5x^5+x^5\right)+\left(-4x^4+2x^4\right)+\left(-2x^3-2x^3\right)+\left(4x^2+3x^2\right)+\left(3x-x\right)+\left(6+\frac{1}{4}\right)\\ =6x^5-2x^4-4x^3+7x^2+2x+\frac{25}{4}\)

a) Ta có: \(A\left(x\right)=2x^5-3x^3+7x-6x^4+2x^3+2\)

\(=2x^5-6x^4-x^3+7x+2\)

Ta có: \(B\left(x\right)=x^5-3x^3+7x-6x^2+x^5+2x^2\)

\(=2x^5-3x^3-4x^2+7x\)

b) Ta có: \(A\left(x\right)-B\left(x\right)\)

\(=2x^5-6x^4-x^3+7x+2-\left(2x^5-3x^3-4x^2+7x\right)\)

\(=2x^5-6x^4-x^3+7x+2-2x^5+3x^3+4x^2-7x\)

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

Ta có: \(A\left(x\right)+B\left(x\right)\)

\(=2x^5-6x^4-x^3+7x+2+2x^5-3x^3-4x^2+7x\)

\(=4x^5-6x^4-4x^3-4x^2+14x+2\)

c) Ta có: C(x)+2A(x)=B(x)

\(\Leftrightarrow C\left(x\right)=B\left(x\right)-2\cdot A\left(x\right)\)

\(\Leftrightarrow C\left(x\right)=2x^5-3x^3-4x^2+7x-2\cdot\left(2x^5-6x^4-x^3-7x+2\right)\)

\(\Leftrightarrow C\left(x\right)=2x^5-3x^3-4x^2+7x-4x^5+12x^4+2x^3+14x-4\)

\(\Leftrightarrow C\left(x\right)=-2x^5+12x^4-x^3-4x^2+21x-4\)

Tên chữ Cam là sao

Bài 1:

a) -6x + 3(7 + 2x)

= -6x + 21 + 6x

= (-6x + 6x) + 21

= 21

b) 15y - 5(6x + 3y)

= 15y - 30 - 15y

= (15y - 15y) - 30

= -30

c) x(2x + 1) - x²(x + 2) + (x³ - x + 3)

= 2x² + x - x³ - 2x² + x³ - x + 3

= (2x² - 2x²) + (x - x) + (-x³ + x³) + 3

= 3

d) x(5x - 4)3x²(x - 1) ??? :V

Bài 2:

a) 3x + 2(5 - x) = 0

<=> 3x + 10 - 2x = 0

<=> x + 10 = 0

<=> x = -10

=> x = -10

b) 3x² - 3x(-2 + x) = 36

<=> 3x² + 2x - 3x² = 36

<=> 6x = 36

<=> x = 6

=> x = 5

c) 5x(12x + 7) - 3x(20x - 5) = -100

<=> 60x² + 35x - 60x² + 15x = -100

<=> 50x = -100

<=> x = -2

=> x = -2

Nãy giờ gửi 2 cái ảnh mà mãi ko lên 😭😭😭

\(a,\)

\(A\left(x\right)+B\left(x\right)=\left(-5+x^2-4x+3x^3-3x^5\right)+\left(-x^5+2x-2x^3+6x^4-7\right)\)

\(=-5+x^2-4x+3x^3-3x^5-x^5+2x-2x^3+6x^4-7\)

\(=-4x^5+6x^4+x^3+x^2-2x-12\)

\(A\left(x\right)-B\left(x\right)=\left(-5+x^2-4x+3x^3-3x^5\right)-\left(-x^5+2x-2x^3+6x^4-7\right)\)

\(=-5+x^2-4x+3x^3-3x^5+x^5-2x+2x^3-6x^4+7\)

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

\(B\left(x\right)-A\left(x\right)=\left(-x^5+2x-2x^3+6x^4-7\right)-\left(-5+x^2-4x-3x^3-3x^5\right)\)

\(=-x^5+2x-2x^3+6x^4-7+5-x^2+4x+3x^3+3x^5\)

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

\(b,\)

\(thay\)\(x=1\)\(vào\)\(đa\)\(thức\)\(B\left(x\right)\)\(ta\)\(có\)\(:\)

\(B\left(1\right)=-1^5+2\cdot\left(-1\right)-2\cdot\left(-1\right)^3+6\cdot\left(-1\right)^4-7\)

\(=-1-2+2+6-7=-2\)

\(Vậy\)\(x=1\)\(không\)\(là\) \(nghiệm\)\(của\)\(đa\)\(thức\)\(B\left(x\right)\)

\(Bạn\)\(xem\)\(lại\)\(đề\) \(nha\)