2,34 : (2,34 - 1,09) x 35 + 21,086 

= 2,34 : 1,25 x 35 + 21,086

= 1,872 x 35 + 21,086

= 65,52 + 21,086 86,606

Chúc bạn học tốt !!!!!!!!!!!!!!!!!!!!!! 

2,34 : ( 2,34 - 1,09 ) × 35 + 21,086

= 2,34 : 1,25 × 35 + 21,086

= 1,872 × 35 + 21,086

= 65,52 + 21,085

= 86,606

Cho mk 1 tk nhé

=2,34/1,25*35+21,086

=1,872*35+21,086

=65,52+21,086

=86,606

đúng đấy , k cho mình nha

86,606 nha bạn

86,606 nha bạn

 2,34 : ( 2,34 - 1,09 ) . 35 + 21,086

= 2,34 : 1,25 . 35 + 21,086

= 1,872 . 35 + 21,086

= 65,52 + 21,086

= 86,606

2,34 : ( 2,34 - 1,09 ) . 35 + 21,086 

= 2,34 : 1,25 . 35 + 21,086 

= 1,872 . 35 + 21,086 

= 65,52 + 21,086 

= 86,606 

= 2,34 : 1,25 * 35 + 21,086 

=  1,872 * 35 + 21,086

= 65,52 + 21, 086

= 86,606

Câu 1: Ta có: A = \(x^3+y^3+3xy=x^3+y^3+3xy\times1=x^3+y^3+3xy\left(x+y\right)\)

\(=\left(x+y\right)^3=1^3=1\)

Câu 2: Ta có: \(B=x^3-y^3-3xy=\left(x-y\right)\left(x^2+xy+y^2\right)-3xy\)

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

Câu 3: Ta có: \(C=x^3+y^3+3xy\left(x^2+y^2\right)-6x^2.y^2\left(x+y\right)\)

\(=x^3+y^3+3xy\left(x^2+2xy+y^2-2xy\right)+6x^2y^2\)

\(=x^3+y^3+3xy\left(x+y\right)^2-3xy.2xy+6x^2y^2\)

\(=x^3+y^3+3xy.1-6x^2y^2+6x^2y^3\)

\(=x^3+y^3+3xy\left(x+y\right)=\left(x+y\right)^3=1^3=1\)

1=13500

2=103500

  1995-321*3-6020:35

=1995-963-172

=1032-712

=320

1995-321x3-6020:35=1995-963-172=1032-172=320

1995 - 321 x 3 - 6020 : 35

=1995 - 963 - 172

=1032 - 172

=320

bạn xài cái này gõ công thức ra đi

a) \(A=\left[\dfrac{x+2}{x^2-x}+\dfrac{x-2}{x^2+x}\right].\dfrac{x^2-1}{x^2-x}\)

\(A=\left[\dfrac{x+2}{x\left(x-1\right)}+\dfrac{x-2}{x\left(x+1\right)}\right].\dfrac{x^2-1}{x^2+2}\)

\(A=\left[\dfrac{\left(x+2\right)\left(x+1\right)+\left(x-2\right)\left(x-1\right)}{x\left(x-1\right)\left(x+1\right)}\right].\dfrac{x^2-1}{x^2+2}\)

\(A=\left[\dfrac{x^2+2x+x+2+x^2-2x-x+2}{x\left(x-1\right)\left(x+1\right)}\right].\dfrac{x^2-1}{x^2+2}\)

\(A=\dfrac{2x^2+4}{x\left(x^2-1\right)}.\dfrac{x^2-1}{x^2+2}\)

\(A=\dfrac{2\left(x^2+2\right)\left(x^2-1\right)}{x\left(x^2-1\right)\left(x^2+2\right)}=\dfrac{2}{x}\)

b) Thay \(x=-200\) vào biểu thức \(A=\dfrac{2}{x}\) ta được :

\(A=\dfrac{2}{x}=\dfrac{2}{-200}=\dfrac{-2}{200}=\dfrac{-1}{100}\)

\(\frac{31}{20}\)đáp số đúng 1000000000000000000000000000000000000000000000000000% đó nha

h and kb nhé

31/20

31/20 là đúng  đó

a) 18,06.4:42+58:25=1,72+2,32=4,04

b) 2,34:(2,34-1,09).3,5-2,006=(2,34:1,25.3,5)-2,006=6,552-2,006=4,546