f(-1)=2×(-1)^2-3×(-1)-2=2-3-2= -3
f(2)=2(2)^2-3×2-2=8-6-2=0
7=2(k)^2-3k-2
2(k)^2-3k-9=0
D=9-4×2×(-9)=81
f(-1)=2×(-1)^2-3×(-1)-2=2-3-2= -3
f(2)=2(2)^2-3×2-2=8-6-2=0
7=2(k)^2-3k-2
2(k)^2-3k-9=0
D=9-4×2×(-9)=81