Question

let r(t)=(sint, cost,t) find k(t)

Answer 1

k(t)=|r'(t)xr''(t)| / |r'(t)|^3

Answer 2

r'(t)= (cost,-sint,1)
r''(t)=(-sint,-cost,0)
|r'(t)|= square root of 2

Answer 3

r'(t)r''(t)=(-sint cost, sint cost, 0)
|r'(t)r''(t)|=root(sin^2t cos^2t+sin^2t cos^2+0)
|r'(t)r''(t)|=root(2 sint^2t cos^2t)=sint.cost root(2)
|r't|^3=2root (2)
k(t)=(sint*cos t)/2

Answer 4

mm,,, in the cross product i got
(-cost, sint,-1)

Answer 5

|dT/dt| x 1/|v|

Answer 6

T = v(t)/|v(t)|

Answer 7

r(t)=(sint, cost,t) find k(t)
r'(t)=<cos(t),-sin(t),1>
r"(t)=<-sin(t),-cos(t),0>
r'(t)xr"(t) = <cos(t),-sin(t),-1>
|r'(t)xr"(t)| = sqrt(2)
|r'(t)| = sqrt(2)
|r'(t)xr"(t)| / |r'(t)|^3 = sqrt(2)/sqrt(2)^3 = 1/2

Answer 8

yea thats what i have

Answer 9

Great!