Răspuns:
c(t)=(3t²,3t-t³) P t=1
{x(t)=3t²
{y(t)=3t-t³
x`(t)=6t
x``(t)=6
y`(t)=3-3t²
y``(t)= -6t
k=[-6t*6t-6(3-3t²)]/[(6t)²+(3-3t²)²]^(3/2)=
(-36t²-18+18t²)/(36t²+9-6t²+81t⁴)^(3/2)=
(-18t²-18)/(81t⁴+30t²+9)^(3/2)=k
k(1)=(-18*1-18)/(81*1+30*1+9)^(3/2)=
-36/(81+30+9)^(3/2)=
-36/120^(3/2)=
-36/120*√120=
-3/5*2√30=-3/10√30
Explicație pas cu pas:
