Question

equaçao do 2 grau (×+1)²-×=7 e (×-1)²-3×=1 em R

Answer 1

(x+1)² -x = 7
x² + 2.x.1 +1² -x = 7
x² +2x +1 -x = 7
x² +2x -x +1 -7
x² +x -6
Δ=b² -4ac
Δ= 1²-4.1.(-6)
Δ= 1 +24
Δ=25

x= -b +/- √Δ / 2a
x= -1 +/- √25 / 2.1
x'= -1 +5 / 2
x'= 4 /2
x'= 2

x''= -1 -5 / 2
x''= -6 /2
x''= -3

(x-1)² -3x = 1
x² -2.x.(-1) +1² -3x = 1
x² +2x +1 -3x = 1
x² +2x -3x +1 = 1
x² -x +1 -1
x² -x +0
Δ= b² -4ac
Δ= (-1)² -4.1.0
Δ= 1 

x= -b +/- √Δ / 2a
x= -1 +/- √1 / 2.1
x'= -1 + 1 /2
x'= 0/2
x'= 0

x''= -1 -1 /2
x''= -2/2
x''= -1

Bons estudos!