=> 2      [   \(P\left(x\right)+Q\left(x\right)+G\left(x\right)\)]= \(x^3+6x^2+5x-4+2x^2+5x^2-x-3-x^3+3x^2-6x+5=16x^2-2x-12\)

=>\(P\left(x\right)+Q\left(x\right)+G\left(x\right)=8x^2-x-6\)

=> \(G\left(x\right)=2x^2-x^3-6x-2\), \(P\left(x\right)=x^2-3\), \(Q\left(x\right)=x^3+5x^2+5x-1\)

đúng cái đi

Câu hỏi đâu rồi bạn?

Bạn phải cho câu hỏi chứ , viết thế này ai hiểu

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

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

mk làm ra đến đây rồi, bạn tự làm tp nhé, phần sau dễ thôi

sau đó thay h(-1) vào rồi tính nhé

câu sau làm tương tự

a)f(x)+g(x)=\(x^5-4x^4-2x^2-7-2x^5+6x^4-2x^2+6.\)

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

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

=\(3x^5-10x^4-13\)

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

=\(x^4+9x^3-11x^2+7x-2\)

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

=\(9x^4+5x^3-x^2-x-12\)

a ) 

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

\(\Rightarrow f\left(x\right)+g\left(x\right)=\left(x^5-2x^5\right)+\left(6x^4-4x^4\right)-\left(2x^2+2x^2\right)+\left(6-7\right)\)

\(\Rightarrow f\left(x\right)+g\left(x\right)=-x^5+2x^4-4x^2-1\)

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

\(\Rightarrow f\left(x\right)-g\left(x\right)=x^5-4x^4-2x^2-7+2x^5-6x^4+2x^2-6\)

\(\Rightarrow f\left(x\right)-g\left(x\right)=\left(x^5+2x^5\right)-\left(4x^4+6x^4\right)+\left(2x^2-2x^2\right)-\left(6+7\right)\)

\(\Rightarrow f\left(x\right)-g\left(x\right)=3x^5-10x^4-13\)

b ) Làm tương tự 

`1)` Yêu cầu là gì ạ?

`2)`

`P(x)-Q(x)=`\((6x^3-3x^2+5x-1)-(-6x^3+3x^2-2x+7)\)

`= 6x^3-3x^2+5x-1+6x^3-3x^2+2x-7`

`= (6x^3+6x^3)+(-3x^2-3x^2)+(5x+2x)+(-1-7)`

`= 12x^3-6x^2+7x-8`

`3)`

`(-3x^3+15x^2+81x):(-3x)`

`= (-3x^3) \div (-3x) + 15x^2 \div (-3x) + 81x \div (-3x)`

`= x^2-5x-27`

help me!!!

b: \(=x^4+x^2+36-2x^3+12x^2-12x+x^2-6x+9\)

\(=x^4-2x^3+14x^2-18x+45\)

\(=x^4+9x^2-2x^3-18x+5x^2+45\)

\(=\left(x^2+9\right)\left(x^2-2x+5\right)\)

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

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

e: \(=3x^4-3x^3-3x^2-2x^3+2x^2+2x+2x^2-2x-2\)

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

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

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

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

Ta có: \(Q\left(x\right)=6x-x^3+5-6x^3-6+7x^2-10x^2\)

\(=\left(-x^3-6x^3\right)+\left(7x^2-10x^2\right)+6x+\left(5-6\right)\)

\(=-7x^3-3x^2+6x-1\)

b) Ta có: P(x)+Q(x)

\(=6x^3-4x^2+4x-2-7x^3-3x^2+6x-1\)

\(=-x^3-7x^2+10x-3\)

Ta có: P(x)-Q(x)

\(=6x^3-4x^2+4x-2+7x^3+3x^2-6x+1\)

\(=13x^3-x^2-2x-1\)