Question

CALCULA RAIZ -X² +2X+3=0

Answer 1

CALCULA RAIZ 
Raiz ( x' e x")
-X² +2X+3=0
a = - 1
b = 2
c = 3
Δ = b² - 4ac
Δ = 2² - 4(-1)(3)
Δ = + 4 + 12
Δ = 16   -----------------------> √Δ = 4 porque √16 = 4
se
Δ > 0 ( DUAS raízes diferentes)
(baskara)

x = - b + √Δ/2a

x' = - 2 + √16/2(-1)
x' = - 2 + 4/-2
x' = +2/-2
x' = - 2/2
x' = - 1
e
x" = - 2 - √16/2(-1)
x" = - 2 - 4/-2
x" = - 6/-2
x" =   +6/2
x" = 3

então

x' = - 1
x" = 3