(1) Find the equations of the tangent and the normal lines to the

(1) Find the equations of the tangent and the normal
lines to the graph of the given function at the indicated
x value.
(a) f (x) = sec
()
x 4
at x = π
June 16, 2014
1 / 29
()
June 16, 2014
2 / 29
√
(b) g(x) = x 3 x
()
at x = 8
June 16, 2014
3 / 29
()
June 16, 2014
4 / 29
(2) Use the differentiation rules to find the first
derivative.
1
(a) y = 4x 3 − √
x
(b) f (t) =
()
√
cos t
June 16, 2014
5 / 29
(c) r (θ) = sin θ tan2 θ
()
June 16, 2014
6 / 29
(d) y =
x + sin x
x 5 + 2x 2
()
June 16, 2014
7 / 29
(e) u =
√
4
()
x sec(2x)
June 16, 2014
8 / 29
3
(f) f (x) = cot
x
()
June 16, 2014
9 / 29
(3) Find
dy
dx .
(a) xy+cos y = tan x
()
June 16, 2014
10 / 29
(b) x 2 +y 2 =
()
p
x − 2y
June 16, 2014
11 / 29
(c) x 2/3 +y 2/3 = 1
()
June 16, 2014
12 / 29
(4) Find
d 2y
dx 2
()
in terms of x and y given xy + y 2 = 2.
June 16, 2014
13 / 29
()
June 16, 2014
14 / 29
(5) Find the equation of the line tangent to the curve of
x sin 2y = y cos 2x at the point (π/4, π/2).
()
June 16, 2014
15 / 29
(6) The volume of a cube is increasing at a rate of
1200 cm3 /min at the instant that its edges are 20 cm
long? At what rate are the lengths of the edges
changing at that instant?
()
June 16, 2014
16 / 29
()
June 16, 2014
17 / 29
(7) A stone dropped into a still pond sends out a
circular ripple whose radius increases at a constant
rate of 3 ft/sec. How fast is the area enclosed by the
ripple increasing at the end of 10 sec?
()
June 16, 2014
18 / 29
()
June 16, 2014
19 / 29
(8)
Two commercial airplanes are flying at 40,000 ft along straight-line
courses that intersect at right angles. Plane A is approaching the
intersection point at a speed of 442 knots1 while plane B is
approaching the intersection point at 481 knots. At what rate is the
distance between the planes changing when A is 5 and B is 12
nautical miles from the intersection?
1
knots are nautical miles per hour and one nautical mile is 2000 yds
()
June 16, 2014
20 / 29
()
June 16, 2014
21 / 29
()
June 16, 2014
22 / 29
(9) A particle is moving along the x-axis so that its
position s in feet at time t in seconds satisfies
s = t 4 − 8t 3 + 10t 2 − 4,
t ≥ 0.
(a) Determine the average velocity over the interval [0, 1]
()
June 16, 2014
23 / 29
s = t 4 − 8t 3 + 10t 2 − 4,
t ≥0
(b) Find the velocity of the particle.
(c) Find the acceleration of the particle.
()
June 16, 2014
24 / 29
s = t 4 − 8t 3 + 10t 2 − 4,
t ≥0
(d) Over which intervals is the particle moving to the left, and over
which is it moving to the right?
()
June 16, 2014
25 / 29
s = t 4 − 8t 3 + 10t 2 − 4,
t ≥0
(e) At which times is the particle at rest?
()
June 16, 2014
26 / 29
s = t 4 − 8t 3 + 10t 2 − 4,
t ≥0
Argue, with some solid mathematics, that at some moment between
t = 0 and t = 7 sec, the particle must be at the origin.
()
June 16, 2014
27 / 29
()
June 16, 2014
28 / 29
()
June 16, 2014
29 / 29