find parametric equations for the tangent line to the curve with the given parametric equations at the…

find parametric equations for the tangent line to the curve with the given parametric equations at the specified point. x = e^(-4t) cos(4t), y = e^(-4t) sin(4t), z = e^(-4t), (1, 0, 1) (x(t), y(t), z(t)) = (⟨-1/√3, 1/√3, -1/√3⟩)
Answer
Explanation:
Step1: Find the value of (t)
Set (x = e^{-4t}\cos(4t)=1), (y = e^{-4t}\sin(4t)=0), (z = e^{-4t}=1). From (z = e^{-4t}=1), we get (t = 0).
Step2: Differentiate (x,y,z) with respect to (t)
Using the product - rule ((uv)^\prime=u^\prime v + uv^\prime), where for (x = e^{-4t}\cos(4t)), (u = e^{-4t}), (u^\prime=-4e^{-4t}), (v=\cos(4t)), (v^\prime=- 4\sin(4t)), so (x^\prime(t)=-4e^{-4t}\cos(4t)-4e^{-4t}\sin(4t)). For (y = e^{-4t}\sin(4t)), (u = e^{-4t}), (u^\prime=-4e^{-4t}), (v=\sin(4t)), (v^\prime = 4\cos(4t)), so (y^\prime(t)=-4e^{-4t}\sin(4t)+4e^{-4t}\cos(4t)). For (z = e^{-4t}), (z^\prime(t)=-4e^{-4t}).
Step3: Evaluate the derivatives at (t = 0)
Substitute (t = 0) into (x^\prime(t)), (y^\prime(t)) and (z^\prime(t)). (x^\prime(0)=-4e^{0}\cos(0)-4e^{0}\sin(0)=-4), (y^\prime(0)=-4e^{0}\sin(0)+4e^{0}\cos(0)=4), (z^\prime(0)=-4e^{0}=-4).
Step4: Write the parametric equations of the tangent line
The parametric equations of a line passing through the point ((x_0,y_0,z_0)=(1,0,1)) with direction - vector (\langle x^\prime(0),y^\prime(0),z^\prime(0)\rangle=\langle - 4,4,-4\rangle) are (x(t)=x_0+x^\prime(0)t=1-4t), (y(t)=y_0 + y^\prime(0)t=4t), (z(t)=z_0+z^\prime(0)t=1-4t).
Answer:
((x(t),y(t),z(t))=(1 - 4t,4t,1 - 4t))