Question

calculati
(a+x+2)^2+(a-1)^3-x(x-1)
(x+2y+3)^2+(2y-x-3)^2
(x-3y)^3+(y+2)^3+(x+y-2)^2

Answer 1

Răspuns:

Explicație pas cu pas:

Answer 2

Raspuns:

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

= a² + x² + 4 + 2( ax + 2 a + 2 x ) + a³-1 - 3a(a-1) - x² + x =

= a² + x² + 4 + 2 a x + 4 a + 4 x + a³- 1 - 3 a² + 3 a - x² + x=

= a³ - 2 a² + 2 a x + 7 a + 5 x + 3

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( x + 2 y + 3 )² + ( 2 y - x - 3)²= 2 x² + 8 y² + 18  + 12 x

( x + 2 y + 3 )²+  = x² + 4 y² + 9 + 4 x y + 12 y + 6 x  

(2 y - x - 3 )²       = x² + 4 y² + 9 - 4 x y - 12 y + 6 x              

                      ___________________________

                       = 2 x² + 8 y² + 18  + 12 x

__________  ____________________________________

( x - 3 y)³ + ( y + 2)³ + ( x + y - 2 )² =

(x-3y)³ = x³ - 27y³ - 9 xy(x-3y) = x³ - 27 y³ - 9 x²y + 27 x y²

(y+2)³ =  y³ + 8     + 6 y(y+2)   =        y³ + 8 + 6 y² + 12 y

( x + y - 2)² = x² + y² + 4 + 2 x y - 4 y - 4 x

  ______________________________________ +

=  x³ - 26 y³+x² + 7 y² + 27 x y² - 9 x²y+2xy + 8 y - 4 x + 12