e: \(\left(a^2-1\right)\left(a^2+a+1\right)\left(a^2-a+1\right)\)

\(=\left(a^3-1\right)\left(a^3+1\right)\)

\(=a^6-1\)

lm hết giúp mk vs

1: =(8+a^3)(8-a^3)=64-a^6

2: =x^3-6x^2+12x-8-x(x^2-1)+6x^2-18x

=x^3-6x-8-x^3+x

=-5x-8

3: =x^3+3x^2+3x+1-x^3+1-3x^2-3x

=2

\(3,\\ a,=a^2+2a+1-a^2+2a-1-3a^2+3=-3a^2+4a+3\\ b,=\left(m^3-m+1-m^2+3\right)^2=\left(m^3-m^2-m+4\right)^2\\ 4,\\ a,\Leftrightarrow25x^2+10x+1-25x^2+9=3\\ \Leftrightarrow10x=-7\Leftrightarrow x=-\dfrac{7}{10}\\ b,\Leftrightarrow-9x^2+30x-25+9x^2+18x+9=30\\ \Leftrightarrow48x=46\Leftrightarrow x=\dfrac{23}{24}\\ c,\Leftrightarrow x^2+8x+16-x^2+1=16\\ \Leftrightarrow8x=-1\Leftrightarrow x=-\dfrac{1}{8}\)

Bài 1

a) 3 2/5 - 1/2

= 17/5 - 1/2

= 34/10 - 5/10

= 29/10

b) 4/5 + 1/5 × 3/4

= 4/5 + 3/20

= 16/20 + 3/20

= 19/20

c) 3 1/2 × 1 1/7

= 7/2 × 8/7

= 4

d) 4 1/6 : 2 1/3

= 25/6 : 7/3

= 25/14

Bài 2

a) 3 × 1/2 + 1/4 × 1/3

= 3/2 + 1/12

= 18/12 + 1/12

= 19/12

b) 1 4/5 - 2/3 : 2 1/3

= 9/5 - 2/3 : 7/3

= 9/5 - 2/7

= 63/35 - 10/35

= 53/35

Bài 4:

a: \(=1-\left(x-y\right)^2\)

\(=\left(1-x+y\right)\left(1+x-y\right)\)

b: \(=a^2-2ab+b^2-c^2+2cd-d^2\)

\(=\left(a-b\right)^2-\left(c-d\right)^2\)

\(=\left(a-b-c+d\right)\left(a-b+c-d\right)\)

d: \(=x^2\left(x^6-64\right)\)

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

Bài 2: 

a: Ta có: \(x\left(2x-1\right)-2x+1=0\)

\(\Leftrightarrow\left(2x-1\right)\left(x-1\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\\x=1\end{matrix}\right.\)