Answer:the first one
Step-by-step explanation:
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)
Those are the answers for 12,13,14,15
<h3>
Answer: Choice D) </h3>
Work Shown:

We must require that
and
to avoid having 0 in the denominator. This is why choice D is the answer.
Answer:
GK=JK
Step-by-step explanation:
SSS congruency is side-side-side congruency. We are given that GH=JH and KH=KH, which are both sides.
For SSS, we need 3 pairs of congruent sides. We already have 2 pairs.
The options are:
<G=<J
<H=<H
GK=JK
the first two options, <G=<J and <H=<H are talking about congruent angles. We don't need to know about congruent angles for SSS
GK=JK is talking about a pair of congurent sides. Then, we would have 3 pairs of congruent sides, satisfying the criteria needed for SSS. Therefore, we must know that GK=JK.
Hope this helps!