What is the arclength of #f(t) = (t-sqrt(t^2+2),t+te^(t-2))# on #t in [-1,1]#?

1 Answer

Arc length #s=3.2352212144206" "#units

Explanation:

The formula to obtain the arc length #s#

#s=int_(t_1)^(t_2) sqrt((dx/dt)^2+(dy/dt)^2)*dt#

From the given #f(t)=(t-sqrt(t^2+2), t+t*e^(t-2))#

We have #x=t-sqrt(t^2+2)" "#and #y= t+t*e^(t-2)#

We need to obtain the derivatives #(dx)/dt# and #(dy)/dt#

#(dx)/dt=1-t/sqrt(t^2+2)" "# and #(dy)/dt=1+t*e^(t-2)+e^(t-2)#

We solve now the arclength #s#

#s=int_(t_1)^(t_2) sqrt((dx/dt)^2+(dy/dt)^2)*dt#

#s=int_(-1)^(1) sqrt((1-t/sqrt(t^2+2))^2+(1+t*e^(t-2)+e^(t-2))^2)*dt#

The integral is complicated and requires the use of calculator or Simpson's Rule formula

#s=int_(-1)^(1) sqrt((1-t/sqrt(t^2+2))^2+(1+t*e^(t-2)+e^(t-2))^2)*dt#

#s=3.2352212144206" "#units

God bless....I hope the explanation is useful.