Question

Rezolvati inmultimea in ecuatii :
(x-1)(x+3)=0
(x+2)(x+3)=12
(3x-6)(4x-3)=0
X la puterea a 2-a +x=6

Answer 1

Răspuns:

a ) S = { - 3 ; 1 } , b ) S = { - 6 , 1 } , c ) { 3 / 4 ; 2 } , d )S = { - 3 , 2 }

Explicație pas cu pas:

Bună! ʕ•́ᴥ•̀ʔっ

a ) ( x - 1 )( x + 3 ) = 0

x - 1 = 0

x = 0 + 1

x = 1

x + 3 = 0

x = 0 - 3

x =  - 3

S = { - 3 ; 1 }

b ) ( x + 2 )( x + 3 ) = 12

x² + 3x + 2x + 6 = 12

x² + 5x + 6 = 12

x² + 5x + 6 - 12 = 0

x² + 6x - x - 6 = 0

x( x + 6 ) - ( x + 6 ) = 0

( x + 6 )( x - 1 ) = 0

x + 6 = 0

x = 0 - 6

x = - 6

x - 1 = 0

x = 0 + 1

x = 1

S = { - 6 , 1 }

c ) ( 3x - 6 )( 4x - 3 ) = 0

3x - 6 = 0

3x = 0 + 6

3x = 6

x = 6 : 3

x = 2

4x - 3 = 0

4x = 0 + 3

4x = 3

x = 3 / 4

{ 3 / 4 ; 2 }

d ) x² + x = 6

x² + x - 6 = 0

x² + 3x - 2x - 6 = 0

x( x + 3 ) - 2( x + 3 ) = 0

( x + 3 )( x - 2 ) = 0

x + 3 = 0

x = 0 - 3

x = - 3

x - 2 = 0

x = 0 + 2

x = 2

S = { - 3 , 2 }