Svpppp je n’y arrive pas en maths

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A ( x) = ( 2 x + 1)² - ( x - 1)²

A ( 1) = ( 2 + 1 )² - ( 2 - 1 )² = 3² + 1² = 9 + 1 = 10  

A(0) = 1 ²  - ( - 1)² = 1 + 1 = 2

A(x ) = 4 x² + 4 x + 1 - ( x² + 2 x + 1 ) = 4 x² + 4 x + 1 - x² - 2 x - 1 = 3 x² + 2 x

A (x) = 3 x²

( 2 x + 1 )² - ( x - 1)² = 3 x²

( 2 x + 1 + x - 1) ( 2 x + 1 - x + 1 ) = 3 x²

3 x ( x + 2 ) = 3 x²

3 x² + 6 x = 3 x²

3 x² - 3 x² +  6 x = 0

6 x = 0

x = 0

A ( x) = 0

( 2 x + 1 )² - ( x - 1)² = 0

( 2 x + 1 + x - 1 ) ( 2 x + 1 - x + 1 ) = 0

3 x ( x + 2 ) = 0

soit  3 x = 0 et x = 0

soit x + 2 = 0 et x = - 2