Answer:
a) 25.15
b)
x = 1
y = t
z = (4pi)^2 + t *(8pi) = 4pi(4pi + 2t)
c) (x,y) = (1, -2pi)
Step-by-step explanation:
a)
First lets calculate the velocity, that is, the derivative of c(t) with respect to t:
v(t) = (-sin(t), cos(t), 2t)
The velocity at t0=4pi is:
v(4pi) = (0, 1, 8pi)
And the speed will be:
s(4pi) = √(0^2+1^2+ (8pi)^2) = 25.15
b)
The tangent line to c(t) at t0 = 4pi has the parametric form:
(x,y,z) = c(4pi) + t*v(4pi)
Since
c(4pi) = (1, 0, (4pi)^2)
The tangent curve has the following components:
x = 1
y = t
z = (4pi)^2 + t *(8pi) = 4pi(4pi + 2t)
c)
The intersection with the xy plane will occurr when z = 0
This happens at:
t1 = -2pi
Therefore, the intersection will occur at:
(x,y) = (1, -2pi)
<span>Simplifying
12 + -6(w + -3) = 3(-5 + -3w) + 21
Reorder the terms:
12 + -6(-3 + w) = 3(-5 + -3w) + 21
12 + (-3 * -6 + w * -6) = 3(-5 + -3w) + 21
12 + (18 + -6w) = 3(-5 + -3w) + 21
Combine like terms: 12 + 18 = 30
30 + -6w = 3(-5 + -3w) + 21
30 + -6w = (-5 * 3 + -3w * 3) + 21
30 + -6w = (-15 + -9w) + 21
Reorder the terms:
30 + -6w = -15 + 21 + -9w
Combine like terms: -15 + 21 = 6
30 + -6w = 6 + -9w
Solving
30 + -6w = 6 + -9w
Solving for variable 'w'.
Move all terms containing w to the left, all other terms to the right.
Add '9w' to each side of the equation.
30 + -6w + 9w = 6 + -9w + 9w
Combine like terms: -6w + 9w = 3w
30 + 3w = 6 + -9w + 9w
Combine like terms: -9w + 9w = 0
30 + 3w = 6 + 0
30 + 3w = 6
Add '-30' to each side of the equation.
30 + -30 + 3w = 6 + -30
Combine like terms: 30 + -30 = 0
0 + 3w = 6 + -30
3w = 6 + -30
Combine like terms: 6 + -30 = -24
3w = -24
Divide each side by '3'.
w = -8
Simplifying
w = -8</span>
