`a, (3x-1)^3-(3x+1)^3`

`= (3x-1-3x-1)(9x^2-6x+1+9x^2-1+9x^2+6x+1`

`= (-2)(27x^2 +1)`

`= -54x^2-2`.

`b, (1+3x)^3 - (1-3x)^3`

`= 1+ 9x + 27x^2 + 27x^3 - 1 + 9x - 27x^2 + 27x^3`

`= 54x^3 + 18x`.

`c, = 54x^3 + 18x -1 +9x^2`.

a: =27x^3-27x^2+9x-1-27x^3-27x^2-9x-1

=-54x^2-2

b: =27x^3+27x^2+9x+1-27x^3+27x^2-9x+1

=54x^2+2

c: =54x^2+2+(3x-1)(3x+1)

=54x^2+2+9x^2-1

=63x^2+1

\(B=\left(x-3\right)^3-\left(x+3\right)\left(x^2-3x+9\right)+\left(3x-1\right)\left(3x+1\right)\)

\(B=x^3-9x^2+27x-27-\left(x^3-3x^2+9x+3x^2-9x+27\right)+\left(9x^2-1\right)\)

\(B=x^3-9x^2+27x-27-\left(x^3+27\right)+9x^2-1\)

\(B=x^3-9x^2+27x-27-x^3-27+9x^2-1\)

\(B=27x-55\)

giải cho tui cả phần c nx đi

Yêu cầu đề bài của bạn?

đề bài : Tính

C=(3x+2)³-18x.(3x+2)+(x-1)³-28x³+3x.(x-1)

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

=3x^3(3^3-3x+1)+3x(3^3-3x+1)+1(3^3-3x+1)-(3x^3)^2+2.3x^3.1+1^2

=3^4x^3-3^2x^4+3x^3+3^4x-3^2x^2+3x+3^3-3x+1-3^2x^6+6x^3+1

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

=x^3(3^4+3)-3^2(x^4-x^6-x^2)+102-3x

=84x^3-9.(x^4-x^6-x^2)+102-3x

1: \(=6x^2+2x-15x-5-x^2+6x-9+4x^2+20x+25-27x^3-27x^2-9x-1\)

=-27x^3-18x^2+4x+10

2: =4x^2-1-6x^2-9x+4x+6-x^3+3x^2-3x+1+8x^3+36x^2+54x+27

=7x^3+37x^2+46x+33

5:

\(=25x^2-1-x^3-27-4x^2-16x-16-9x^2+24x-16+\left(2x-5\right)^3\)

\(=8x^3-60x^2+150-125+12x^2-x^3+8x-60\)

=7x^3-48x^2+8x-35

   R(x) =           2x² + 3x - 1

^-  M(x) =   -x³ + x² 

                x³ + x² + 3x - 1

Vậy R(x) - M(x) = x³ + x² + 3x - 1

g: Ta có: \(3\left(2x-1\right)\left(3x-1\right)-\left(2x-3\right)\left(9x-1\right)=0\)

\(\Leftrightarrow3\left(6x^2-5x+1\right)-\left(18x^2-29x+3\right)=0\)

\(\Leftrightarrow18x^2-15x+3-18x^2+29x-3=0\)

\(\Leftrightarrow14x=0\)

hay x=0

w

Tập xác định của phương trình

2

Rút gọn thừa số chung

3

Giải phương trình

4

Biệt thức

5

Biệt thức

6

Nghiệm

7

Lời giải thu được

a) 3/2.|x - 5/3| - 4/5 = 4/3.|x - 5/3| + 1

<=> 3/2.|x - 5/3| = 4/3.|x - 5/3| + 1 + 4/5

<=> 3/2.|x - 5/3| = 9/5 + 4|x - 5/3|/3

<=> 3/2.|x - 5/3| - 4.|x - 5/3|/3 = 9/5

<=> |x - 5/3|/6 = 9/5

<=> |x - 5/3| = 9/5.6

<=> |x - 5/3| = 54/5

<=> x - 5/3 = 54/5 hoặc x - 5/3 = -54/5

       x = 54/5 + 5/3         x = -54/5 - 5/3

       x = 187/15              x = -137/15

b) 2.|3x + 1| = 1/3.|3x + 1| + 5

<=> 2.|3x + 1| - 1/3.|3x + 1| = 5

<=> 5/3.|3x + 1| = 5

<=> 5.|3x + 1| = 5.3

<=> 5.|3x + 1| = 15

<=> |3x + 1| = 15 : 5

<=> |3x + 1| = 3

       3x + 1 = 3 hoặc 3x + 1 = -3 

       3x = 3 - 1           3x = -3 - 1

       3x = 2                3x = -4

       x = 2/3               x = -4/3

=> x = 2/3 hoặc x = -4/3

c) làm tương tự câu a) mình hơi lời

Làm câu c) cho

\(\frac{1}{4}-\frac{5}{2}\left|3x-\frac{1}{5}\right|=\frac{2}{3}\left|3x-\frac{1}{5}\right|-\frac{2}{3}\)

\(\Leftrightarrow\frac{1}{4}+\frac{2}{3}=\frac{2}{3}\left|3x-\frac{1}{5}\right|+\frac{5}{2}\left|3x-\frac{1}{5}\right|\)

\(\Leftrightarrow\frac{3}{12}+\frac{8}{12}=\left|3x-\frac{1}{5}\right|\left(\frac{2}{3}+\frac{5}{2}\right)\)

\(\Leftrightarrow\left|3x-\frac{1}{5}\right|\left(\frac{4}{6}+\frac{15}{6}\right)=\frac{11}{12}\)

\(\Leftrightarrow\frac{19}{6}\left|3x-\frac{1}{5}\right|=\frac{11}{12}\)

\(\Leftrightarrow\left|3x-\frac{1}{5}\right|=\frac{11}{12}.\frac{6}{19}\)

\(\Leftrightarrow\left|3x-\frac{1}{5}\right|=\frac{11}{38}\)

\(\Leftrightarrow\orbr{\begin{cases}3x-\frac{1}{5}=\frac{11}{38}\\3x-\frac{1}{5}=-\frac{11}{38}\end{cases}}\)

Giải tiếp nha

\(A=2x^3+3x^2-3-5x^2-5x=2x^3-2x^2-5x-3\\ B=125-150x+60x^2-8x^3-25+9x^2=-8x^3+69x^2-150x+100\\ C=\left(3x+1-2x+1\right)\left(3x+1+2x-1\right)=5x\left(x+2\right)=5x^2+10x\\ D=\left(2x+1-3+x\right)^2=\left(3x-2\right)^2=9x^2-12x+4\\ E=x^3-6x^2+12x-8-x^3+x+6x^2-18x=-5x-8\\ F=x^3-3x^2+3x-1-3+3x^2-x^3+1-3x=-3\)