Toán Lớp 8: x^2+(a+b)x+ab 2022x-2022y+y^2-2xy+x^2 (x-5)^2=(3+2x)^2 X^2(x-2)+2-x=0

Question

Toán Lớp 8:  x^2+(a+b)x+ab 2022x-2022y+y^2-2xy+x^2 (x-5)^2=(3+2x)^2 X^2(x-2)+2-x=0

huenthanh97 · Answer

1. x  &sup2;   + ( a + b )x + ab = x  &sup2;   + ax + bx + ab       1. x&sup2; + ( a + b )x + ab = x&sup2; + ax + bx + ab            2. 2022x - 2022y + y  &sup2;   - 2xy + x  &sup2;         2. 2022x - 2022y + y&sup2; - 2xy + x&sup2;            = 2022( x - y ) + ( y - x )  &sup2;         = 2022( x - y ) + ( y - x )&sup2;            = -2022( y - x ) + ( y - x )  &sup2;      = -2022( y - x ) + ( y - x )&sup2;          = ( y - x )( -2022 + y - x )     = ( y - x )( -2022 + y - x )           3. ( x - 5 )  &sup2;   = ( 3 + 2x )  &sup2;         3. ( x - 5 )&sup2; = ( 3 + 2x )&sup2;           &hArr; x - 5 = 3 + 2x      &hArr; x - 5 = 3 + 2x           &hArr; x - 2x = 3 + 5     &hArr; x - 2x = 3 + 5          &hArr; -x = 8     &hArr; -x = 8          &hArr; x = -8     &hArr; x = -8           4. x  &sup2;  ( x - 2 ) +2 - x = 0      4. x&sup2;( x - 2 ) +2 - x = 0           &hArr; x  &sup2;  ( x - 2 ) - ( x - 2 ) = 0      &hArr; x&sup2;( x - 2 ) - ( x - 2 ) = 0           &hArr; ( x  &sup2;   - 1 )( x - 2 ) = 0      &hArr; ( x&sup2; - 1 )( x - 2 ) = 0     &hArr;         [         x    =    &plusmn;    1          x    =    2             [x=&plusmn;1x=2

dongoclandiem · Answer

$ text{1. x&sup2; + ( a + b )x + ab = x&sup2; + ax + bx + ab }$   $ text{2. 2022x - 2022y + y&sup2; - 2xy + x&sup2; }$   $ text{= 2022( x - y ) + ( y - x )&sup2; }$   $ text{= -2022( y - x ) + ( y - x )&sup2;}$   $ text{= ( y - x )( -2022 + y - x )}$   $ text{3. ( x - 5 )&sup2; = ( 3 + 2x )&sup2; }$   $ text{&hArr; x - 5 = 3 + 2x }$   $ text{&hArr; x - 2x = 3 + 5}$   $ text{&hArr; -x = 8}$   $ text{&hArr; x = -8}$   $ text{4. x&sup2;( x - 2 ) +2 - x = 0}$   $ text{&hArr; x&sup2;( x - 2 ) - ( x - 2 ) = 0}$   $ text{&hArr; ( x&sup2; - 1 )( x - 2 ) = 0}$   &hArr; $ left[ begin{matrix} x= &plusmn;1   x= 2 end{matrix} right.$