Question

rút gọn biểu thức sau : A = ( x-2 ) ^2 + ( x+3 ) ^2 - 2 . ( x + 1) ( x-1)

 

Answer 1

A = (x - 2)² + (x + 3)² - 2.(x + 1)(x - 1)

A = (x - 2)² + (x + 3)² - 2.(x² - 1)

A = x² - 2.2x + 2² + x² + 2.3x + 3² - 2x² + 2

A = 2x + 15

Answer 2

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

\(A=x^2-4x+4+x^2+6x+9-2\left(x^2-1\right)\)

\(A=2x^2+2x+13-2x^2+2\)

\(A=2x+15\)

Answer 3

Ta có:  A = ( x-2 ) ^2 + ( x+3 ) ^2 - 2 . ( x + 1) ( x-1)

<=> A = ( x² - 4x + 4) + ( x² - 6x + 9) - 2. (x² - 1)

<=> A=  ( x² - 4x + 4) + ( x² - 6x + 9) - (2x² - 2)

<=> A=  x² - 4x + 4 + x² - 6x + 9 - 2x²  + 2

<=> A=  - 10x + 15

<=> A=  15 - 10x !!!

Answer 4

kết quả là:

   2x + 15

       đs...

Answer 5

A= 2x + 15

Answer 6

cảm ơn các bạn