Question

l(x)=-x^2+9x-18 qual a resposta destas questôes ?

Answer 1

L(x)=-x^2+9x-18

- x^2 + 9x - 18 = 0

a = - 1; b = 9; c = - 18

∆ = b^2-4ac

∆ = 9^2 - 4.(-1).(-18)

∆ = 81 + 4.(-18)

∆ = 81 - 72

∆ = 9

x = [ - b +/- √∆]/2a

x = [ - 9 +/- √9]/2.(-1)

x = [ - 9 +/- 3]/(-2)

x' = [ - 9 + 3]/(-2) = -6/(-2) = 3

x" = [- 9 - 3]/(-2) = -12/(-2) = 6