Question

preciso do cálculo urgente por favor...

Answer 1

resposta A:
3x²-2x-1=0
Δ=(-2)²-4×3×(-1)
Δ=4+12
Δ=16
4
x'=2+4/2×3=6/6=1
x"=2-4/2×3=-2/6=-1/3

resposta B:
y²-7y+6=0
Δ=(-7)²-4×1×6
Δ=49-24
Δ=25
5
y'=7+5/2×1=12/2=6
y''=7-5/2×1=2/2=1

resposta C:
16x²+8x+1=0
Δ=8²-4×16×1
Δ=64-64
Δ=0
0
x'=8+0/2×16=8/32=I/4
x"=8-0/2×16=8/32=1/4

resposta D:
5x²-4x+2=0
Δ=(-4)²-4×5×2
Δ=16-40
Δ=24
∉