Răspuns :
Răspuns:
Explicație pas cu pas:
a)
4(5x-3)^2-9(3x-4)^2 =
[2(5x-3)]² - [3(3x-4)]² =
[10x - 6]² - [9x - 12]² =
(10x - 6 + 9x - 12)(10x - 6 - 9x + 12) =
(19x - 18)(x + 6)
b)
2x^2 - x - 3 =
2x² + 2x - 3x - 3 =
2x(x + 1) - 3(x + 1) =
(x + 1)(2x - 3)
c)
x^2 - 5x - 6 =
= x^2 + x - 6x - 6 =
= x(x+1) - 6(x+1) =
= (x + 1)(x - 6)
a)4(5x-3)²-9(3x-4)²=
2²×(5x-3)²-3²×(3x-4)²=
(2(5x-3))²-(3(3x-4))²=
(2(5x-3)-3(3x-4))(2(5x-3)+3(3x-4))=
(10x-6-9x+12)(10x-6+9x-12)=
(x+6)(19x-18)
b)2x²-x-3=
2x²+2x-3x-3=
2x(x+1)-3(x+1)=
(x+1)(2x-3)
c)x²-5x-6=
x²+x-6x-6=
x(x+1)-6(x+1)=
(x+1)(x-6)