Question

Rezolvați ecuatiile: (x-1)²-4=0

Answer 1

${(x - 1)}^{2} - 4 = 0$

${x}^{2} - 2x + 1 - 4 = 0$

${x}^{2} - 2x - 3 = 0$

${x}^{2} - 3x + x - 3 = 0$

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

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

$x - 3 = 0 = > x = 3$

$x + 1 = 0 = > x = - 1$

Answer 2

(x-1)^2-4=0 =>x^2-2x+1-4=0 =>x^2-2x-3=0
delta=4+12=16
x1=(2+4)/2=3
x2=(2-4)/2=-1