B.6x3-12x2+3x

chac zay

a) ( x 2  – 4x + 1)( x 2  – 2x + 3).

b) ( x 2  + 5x – 1)( x 2  + x – 1).

a) 11/12 + 5/6 x 3/2 - 2/3 

= 11/12 + 15/12 - 2/3

= 26/12 - 2/3

= 26/12 - 8/12

= 18 /12 = 3/2

b) 4/9 : 4/6 x 3/4 +5/3 

= 4/9 x 6/4 x 3/4 + 5/3

= 2/3 x 3/4 + 5/3 

= 6/12 + 5/3 

= 6/12 + 20/12

= 26/12 = 13/6

c) 5/7 : 11/14 : 15/22 x 3/5 

= 5/7 x 14/11 x 22/15 x 3/5 

= 10/11 x 22/15 x 3/5 

= 4/3 x 3/5 = 20/15 = 4/3

a. \(\dfrac{11}{12}+\dfrac{5}{6}\)x\(\dfrac{3}{2}-\dfrac{2}{3}\) \(=\)\(\dfrac{11}{12}+\dfrac{5}{4}-\dfrac{2}{3}=\dfrac{11}{12}+\dfrac{15}{12}-\dfrac{8}{12}=\dfrac{11+15-8}{12}=\dfrac{18}{12}=\dfrac{3}{2}\)

b. \(\dfrac{4}{9}:\dfrac{4}{6}\)x\(\dfrac{3}{4}+\dfrac{5}{3}\)  \(=\dfrac{4}{9}:\dfrac{1}{2}+\dfrac{5}{3}=\dfrac{8}{9}+\dfrac{5}{3}=\dfrac{8}{9}+\dfrac{15}{9}=\dfrac{8+15}{9}=\dfrac{23}{9}\)

c. \(\dfrac{5}{7}:\dfrac{11}{14}:\dfrac{15}{22}\)x\(\dfrac{3}{5}\) \(=\dfrac{10}{14}:\) \(\dfrac{11}{14}:\dfrac{15}{22}\)x\(\dfrac{3}{5}\) \(=\dfrac{10}{11}\)\(:\dfrac{15}{22}\)x\(\dfrac{3}{5}\) \(=\dfrac{20}{22}:\dfrac{15}{22}\)x\(\dfrac{3}{5}\) \(=\dfrac{4}{3}\)x\(\dfrac{3}{5}=\dfrac{4}{5}\)

a: \(P\left(x\right)=6x^3+4x^2+2x-4\)

\(Q\left(x\right)=-x^4+6x^3-4x^2+3x-8\)

b: \(P\left(x\right)-Q\left(x\right)=x^4+8x^2-x+4\)

\(P\left(x\right)+Q\left(x\right)=-x^4+12x^3+5x-12\)

a. M(x) + N(x) = 6x³ – 2x² + 3x +10 - 6x³ + x² – 6x -10

= (6x³ - 6x³ ) + ( -2x² + x² ) + ( 3x - 6x ) + ( 10 - 10 )

= -x² - 3x 

M(x) - N(x) = 6x³ – 2x² + 3x +10 - ( –6x³ + x² – 6x -10)

= 6x³ – 2x² + 3x +10 + 6x³ - x² + 6x +10

= (6x³ + 6x³ ) + ( -2x² - x² ) + ( 3x + 6x) + ( 10 + 10)

= 12x³ - 3x² + 9x + 20

b. Đặt -x² - 3x  = 0

=> -x² + (-3)x = 0

=> -x² + 3.-x = 0

=> -x(-x+ 3) = 0

=>\(\left[{}\begin{matrix}-x=0\\-x+3=0\end{matrix}\right.=>\left[{}\begin{matrix}x=0\\-x=-3\end{matrix}\right.=>\left[{}\begin{matrix}x=0\\x=3\end{matrix}\right.\)

Vậy nghiệm của đa thức trên là 0 hoặc -3

a) M(X) + N(x)= (6x³ – 2x² + 3x +10)

+ (–6x³ + x² – 6x -10)

M(x) + N(x)=  – x² - 3x.

M(x) + N(x)= (6x³ – 2x² + 3x +10)

- (–6x³ + x² – 6x -10)

M(x) - N(x)= 12x³ - x² + 9x + 20.

b) Nghiệm của M(x) + N(x)= x= 0, -3.

It's 6 plus 6 and add 6

the sum of three number 6

5/6x3/5=1/2

5/6 x 3/5

=15/30=3/7

\(\frac{5}{6}x\frac{3}{5}=\frac{1x3}{6x1}=\frac{3}{6}=\frac{1}{2}\)

duyệt đi

7

\(=\left(6x^3+3x^2-10x^2-5x+4x+2\right):\left(2x+1\right)\\ =\left[3x^2\left(2x+1\right)-5x\left(2x+1\right)+2\left(2x+1\right)\right]:\left(2x+1\right)\\ =3x^2-5x+2\)

\(=3x^2-\dfrac{7}{2}x-2+x+6x^3-7x^2+x+2\\ =-4x^2-\dfrac{7}{2}x+6x^3\)