Suppose that the temperature at the point (x, y, z) in space is T(x, y, z) = x2 + y2 + z2. Let a particle follow the right-circular helix σ(t) = (cos(t), sin(t), t) and let T(t) be its temperature at time t. (a) What is T '(t)? T '(t) = (b) Find an approximate value for the temperature at t = π 6 + 0.01.

Respuesta :

Answer with Step-by-step explanation:

We are given that

[tex]T(x,y,z)=x^2+y^2+z^2[/tex]

[tex]\sigma(t)=(cost,sint,t)[/tex]

T(t) be the temperature at time t.

a.Substitute the value of x,y and z

Where [tex]x=cost,y=sint,z=t[/tex]

[tex]T(t)=cos^2t+sin^2t+t^2[/tex]

We know that

[tex]sin^2x+cos^2x=1[/tex]

By using the formula

[tex]T(t)=1+t^2[/tex]

Now, differentiate w.r.t t

[tex]T'(t)=2t[/tex]

b.[tex]t=\frac{\pi}{6}+0.01[/tex]

We have to find the approximate value of the temperature at given value of t.

Substitute [tex]x=\frac{\pi}{6}[/tex]

[tex]T(\frac{\pi}{6})=1+(\frac{\pi}{6})^2=1+\frac{\pi^2}{36}[/tex]

[tex]T'(\frac{\pi}{6})=2\times\frac{\pi}{6}=\frac{\pi}{3}[/tex]

Linear approximation formula:

[tex]f(x)\approx L(x)=f(a)+f'(a)(x-a)[/tex]

Where [tex]a=\frac{\pi}{6}[/tex]

and [tex]t=\frac{\pi}{6}+0.01[/tex]

Substitute the values

The approximate value of the temperature=[tex]T(\frac{\pi}{6})+T'(\frac{\pi}{6})(\frac{\pi}{6}+0.01-\frac{\pi}{6})[/tex]

The approximate value of the temperature=[tex]1+\frac{\pi^2}{36}+\frac{\pi}{3}(0.01)[/tex]

The approximate value of the temperature=[tex]1+\frac{(3.14)^2}{36}+\frac{3.14}{3}\times 0.01=1.284[/tex]

Where [tex]\pi=3.14[/tex]