Question

como faço essa questão (x-2)^2

Answer 1

$(x - 2)^2 \\ \\ (x - 2)*(x - 2) \\ \\ x^2 - 2x -2x + 4 \\ \\ \\ => x^2 -4x + 4 =0$

Resolvendo por Bhaskara:

$x = \dfrac{-b \pm \sqrt{b^2 -4*a*c}}{2*a}$

a=1, b=−4, c=4

Δ=b^2−4ac
Δ=(−4)2−4*(1)*(4)
Δ=16−16
Δ=0

$x = \dfrac{-b \pm \sqrt{\triangle}}{2*a} \\ \\ x = \dfrac{-(-4) \pm \sqrt{0}}{2*1} \\ \\ x = \dfrac{4 \pm 0}{2} \\ \\ x' = \dfrac{4 + 0}{2} \\ \\ x' = \dfrac{4}{2} \\ \\ x' = 2 \\ \\ \\ x'' = \dfrac{4 - 0}{2} \\ \\ x'' = \dfrac{4}{2} \\ \\ x'' = 2$

S ={2}