Question

como descobrir a raiz de b²-4b

Answer 1

$b^2 - 4 = 0 \\ \\ b = \dfrac{-b \pm \sqrt{b^2 -4*a*c}}{2*a}$

a=1, b=−4, c=0

Δ=b2−4ac
Δ=(−4)2−4*(1)*(0)
Δ=16+0
Δ=16

$b = \dfrac{-b \pm \sqrt{\triangle}}{2*a} \\ \\ \\ b = \dfrac{-(-4) \pm \sqrt{16}}{2*1} \\ \\ \\ b = \dfrac{4 \pm 4}{2} \\ \\ \\ b' = \dfrac{4 + 4}{2} \\ \\ \\ b' = \dfrac{8}{2} \\ \\ \\ b' = 4 \\ \\ \\ b'' = \dfrac{4 - 4}{2} \\ \\ \\ b'' = \dfrac{0}{2} \\ \\ \\ b'' = 0$

S = {4, 0}