Math 141.1 - Test I
Tuesday, Sept. 21, 1993
Name
Show your work for full credit
Let f be defined by
f(x) =
ì
í
î
5-x
2
,
if -1
<
x
<
1
2(2-x),
if x
³
1.
Sketch the graph of f.
Determine the domain and range of f.
Is f continuous at the points x = -1,0,1? Verify your answer.
Using the properties of limits, find the the following limits putting in each step:
lim
x
®
3
[(x
2
-4x+3)/(x
2
-9)]
lim
x
®
2
[(x
2
-4x+3)/(x
2
-9)]
lim
x
®
0
[tan(x)/x cos(x)]
Using the definition of derivative and the properties of
limits
, compute the derivative of f at x = 2 where f is given by
f(x) = x
2
+x-3.
Let
f(x) = 2x
3
-6x-2.
Compute the slope of the tangent line to the graph of f when x = 1.
Give the equation of the tangent line to the graph of f at the same point.
For which values of x is the tangent line horizontal?
Using the properties of
derivatives
, determine the derivatives of each of the following functions:
g(x) = (2x
2
-3)(1-2x+x
2
)
f(x) = x
2
e
x
-2x
3
(Hint: You can use D
x
(e
x
) = e
x
)
[EXTRA CREDIT]
Using the definition of `limit', prove that
lim
x
®
0
x
2
= 0.
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