Question

2x²+1=3 equaçao do 2º grau

Answer 1

2x² + 1 = 3 
2x² =  3 - 1
2x² = 2
x² = 2/2
x² = 1
x = √1
x = +- 1   S = { 1, -1 }

Answer 2

2x²+1=3
2x²+1-3=0
2x²-2=0
2x²=2
x²=2/2
x²=+ - 1
x=+ -√1
x=+ -1

Ou:
Δ = b² -4ac
Δ = 0² -4 *2 * (-2)
Δ = 0 + 16
Δ = 16
x' = (-b + √∆)/ 2a
(-0 + 4)/2 * 2
(0 + 4)/4
4/4= 1
x'' = (-b - √∆)/ 2a
(-0 - 4)/2 * 2
(0 - 4)/4
-4/4= -1

S= {1,-1}