Unit 1 Practice Test Filled in

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Name ____Key_____________________________ Date ___________ Period _______
Pre-Calculus Unit 1 Practice Test
Complete the problems below and show your work.
Target 1A: I can identify functions from data tables, graphs, and descriptions of set relations.
1. Does the graph below represent a function? Explain.
y
yes; each π‘₯-value has one 𝑦-value and it
passes the vertical line test
x
2. Does the table represent a function? Explain why or why not.
𝒙
4
1
−3
8
1
π’š
2
6
3
8
9
No; the π‘₯-value of 1 has two different 𝑦values.
3. If 𝑓(π‘₯) = −π‘₯ 2 + 2 evaluate
a. 𝑓(2)
−(2)2 + 2 = −4 + 2 = −2
b. 𝑓(−1)
−(−1)2 + 2 = −1 + 2 = 1
c. 𝑓(3) − 𝑓(1)
𝑓(3) = −(3)2 + 2 = −7 and 𝑓(1) = −(1)2 + 2 = 1 so 𝑓(3) − 𝑓(1) = −7 − 2 = −8
Target 1B: I can describe a set of numbers in a variety of ways.
For each of the following, fill in the missing type of interval or graph. Describe the interval as bounded,
unbounded, open, closed, half-open.
4. Interval
Graph
(3, 7]
Inequality
←
]
0 1 2 3 4 5 6 7
Description π»π‘Žπ‘™π‘“ − π‘œπ‘π‘’π‘› π‘π‘œπ‘’π‘›π‘‘π‘’π‘‘
3<π‘₯≤7
(3, ∞)
5. Interval
Graph
π‘₯>3
Inequality
(
0 1 2 3 4 5 6 7
Description π‘ˆπ‘›π‘π‘œπ‘’π‘›π‘‘π‘’π‘‘ π‘Žπ‘›π‘‘ π‘œπ‘π‘’π‘›
(−∞, 9]
6. Interval
Inequality
π‘₯≤9
Graph
0
9
π‘’π‘›π‘π‘œπ‘’π‘›π‘‘π‘’π‘‘ π‘π‘™π‘œπ‘ π‘’π‘‘
Description__________________
7. Describe the set of numbers using interval notation.
π‘₯ ≥ 5 or π‘₯ < 11
[5, ∞)π‘œπ‘Ÿ (−∞, 11)
(−∞, 11)π‘œπ‘Ÿ [5, ∞)
8. Describe the set of numbers using set-builder notation.
{−9, −8, −7, −6, −5, … }
{π‘₯|π‘₯ ≥ −9, π‘₯ ∈ β„€}
9. Describe the domain and range of 𝑦 = √π‘₯ + 3 in interval notation.
π·π‘œπ‘šπ‘Žπ‘–π‘›: [−3, ∞)
Range: [0, ∞)
10. Use the graph below to find the domain and range.
y
10
8
π·π‘œπ‘šπ‘Žπ‘–π‘›: (−2, −1]π‘ˆ(0, 3]
π‘…π‘Žπ‘›π‘”π‘’: (−7, 6.2]
6
4
2
–10 –8
–6
–4
–2
–2
2
4
6
8
10
x
–4
–6
–8
–10
11. Find the domain and range of the relation {(−2, 4), (3, 5), (4, −2), (3, 8)} and explain if it determines a
function.
π·π‘œπ‘šπ‘Žπ‘–π‘›: {−2, 3, 4}
π‘…π‘Žπ‘›π‘”π‘’: {−2, 4, 5, 8}
Not a function because 3 has two
different 𝑦-values
Target 1C: I can define, interpret, and use piecewise functions in function notation and as a graph.
3π‘₯ − 1 𝑖𝑓 π‘₯ < −3
13. Graph 𝑓(π‘₯) = {π‘₯ + 4 𝑖𝑓 − 3 ≤ π‘₯ < 2
−2 𝑖𝑓 π‘₯ > 2
2π‘₯ + 1 𝑖𝑓 π‘₯ < 0
12. Graph 𝑓(π‘₯) = {
4π‘₯ 𝑖𝑓 π‘₯ ≥ 0
9 y
8
7
6
5
4
3
2
1
-9 -8 -7 -6 -5 -4 -3 -2 -1
-1
-2
-3
-4
-5
-6
-7
-8
-9
14. Graph 𝑓(π‘₯) = {
9 y
8
7
6
5
4
3
2
x
1
-1 1 2 3 4 5 6 7 8 9
-9 -8 -7 -6 -5 -4 -3 -2 -1
-2
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
x
1 2 3 4 5 6 7 8 9
π‘₯ 2 𝑖𝑓 π‘₯ < 0
5π‘₯ 𝑖𝑓 π‘₯ ≥ 0
9 y
8
7
6
5
4
3
2
1
-9 -8 -7 -6 -5 -4 -3 -2 -1
-1
-2
-3
-4
-5
-6
-7
-8
-9
x
1 2 3 4 5 6 7 8 9
15. Write a piecewise function for the graph below.
9
8
7
6
5
4
3
2
1
-9 -8 -7 -6 -5 -4 -3 -2 -1-1
-2
-3
-4
-5
-6
-7
-8
-9
y
−π‘₯ + 3, 𝑖𝑓 π‘₯ < 0
𝑓(π‘₯) = {
−π‘₯ 2 , 𝑖𝑓 π‘₯ ≥ 0
x
1 2 3 4 5 6 7 8 9
16. Rewrite the function in the previous question so that the function would be continuous.
−π‘₯, 𝑖𝑓 π‘₯ < 0
𝑓(π‘₯) = { 2
−π‘₯ , 𝑖𝑓 π‘₯ ≥ 0
17. Write a piecewise function for the graph below.
9
8
7
6
5
4
3
2
1
y
-9 -8 -7 -6 -5 -4 -3 -2 -1-1
-2
-3
-4
-5
-6
-7
-8
-9
π‘₯ 2 , 𝑖𝑓 π‘₯ ≤ 0
𝑓(π‘₯) = {
π‘₯ − 2, 𝑖𝑓 π‘₯ > 0
x
1 2 3 4 5 6 7 8 9
18. Rewrite the function in question 17 so that the function would be continuous.
π‘₯ 2 , 𝑖𝑓 π‘₯ ≤ 0
𝑓(π‘₯) = {
π‘₯ − 2, 𝑖𝑓 π‘₯ > 0
Target 1D: I can determine the average rate of change for a function as well as identify increasing and
decreasing functions and intervals.
19. For which interval(s) is the function 𝑦 = 2π‘₯ 3 − 8π‘₯ + 5 increasing and decreasing?
𝐼𝑛𝑐.: (−∞, −1)π‘ˆ(1.2, ∞)
𝐷𝑒𝑐.: (−1, 1.2)
20. Find the extrema for 𝑓(π‘₯) = −3π‘₯ 3 + 8π‘₯ 2 + 10π‘₯ − 9 name the specific type of extrema.
πΏπ‘œπ‘π‘Žπ‘™ 𝑀𝑖𝑛: (−0.49, −11.63)
πΏπ‘œπ‘π‘Žπ‘™ π‘€π‘Žπ‘₯: (2.27, 19.83)
21. Graph the function 𝑦 = π‘₯ 4 + 2π‘₯ 3 + 3π‘₯ on your calculator. Find the x-value of any extrema to the nearest
hundredth and describe what type of extrema it is.
πΊπ‘™π‘œπ‘π‘Žπ‘™ 𝑀𝑖𝑛 π‘₯ = −1.75
22. Find the average rate of change for 𝑓(π‘₯) = π‘₯ 3 − π‘₯ 2 on the following intervals.
a. [0, 4]
b. [−4, −3]
𝑓(0) = 0
𝑓(4) = 43 − 42 = 48
48 − 0
= 12
4−0
𝑓(−4) = (−4)3 − (−4)2 = −80
𝑓(−3) = (−3)3 − (−3)2 = −36
−36 − −80 44
=
= 44
−3 − −4
1
23. Find the average rate of change for 𝑓(π‘₯) = π‘₯ 2 + π‘₯ on the following intervals.
a. [1, 3]
𝑓(1) = 12 + 1 = 2
𝑓(3) = 32 + 3 = 9 + 3 = 12
12 − 2 10
=
=5
3−1
2
b. [−4, −1]
𝑓(−4) = (−4)2 − 4 = 12
𝑓(−1) = (−1)2 − 1 = 1 − 1 = 0
0 − 12
12
=−
= −4
−1 − (−4)
3
c. [π‘Ž, π‘Ž + β„Ž]
𝑓(π‘Ž) = π‘Ž2 + π‘Ž
𝑓(π‘Ž + β„Ž) = (π‘Ž + β„Ž)2 + π‘Ž + β„Ž = π‘Ž2 + 2π‘Žβ„Ž + β„Ž2 + π‘Ž + β„Ž
(π‘Ž2 + 2π‘Žβ„Ž + β„Ž2 + π‘Ž + β„Ž) − (π‘Ž2 + π‘Ž) π‘Ž2 + 2π‘Žβ„Ž + β„Ž2 + π‘Ž + β„Ž − π‘Ž2 − π‘Ž 2π‘Žβ„Ž + β„Ž2 + β„Ž
=
=
= 2π‘Ž + β„Ž + 1
π‘Ž+β„Ž−π‘Ž
β„Ž
β„Ž
24. Find the average rate of change for the graph below on the interval [−2,0].
y
9
8
7
2
6
5
4
3
2
1
-5
-4
-3
-2
-1
x
1
-1
2
3
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