### Home > CALC > Chapter 11 > Lesson 11.3.2 > Problem11-109

11-109.

No calculator! A particle moves in the plane so that at any time $t$, $0 ≤ t ≤ 1$, its position is given $x =\frac { 1 } { 4 }e^{ 8t} − 2t$ and $y = e^{4t}$ . Find its velocity and speed when $t =\frac { 1 } { 4 }$.

$\text{speed}=\sqrt{(x^\prime(t))^2+(y^\prime(t))^2}$