Question

-x²-3x-2>0 determine em R

Answer 1

-x²- 3x - 2 > 0
-x²- 3x - 2 = 0
Δ= b² - 4ac    a= -1 b=-3 c=-2
Δ=3² - 4·(-1)·(-2)
Δ= 9 - 8
Δ= 1 √Δ=1
(-b +/- √Δ) /2a
( -(-3) +/- 1 ) / 2·(-1)
x'=> (3+1) / -2
        4/ -2 = -2
        x'= -2

x" => (3-1) / -2   
          2/ -2 = -1 
          x" = -1