Test 4 MAT 190 Winter 2009 Name ______________________
This test is take-home, so you may use your notes, book, Excel, MathGV, etc. This test is due back to me
at the beginning of class on Tuesday, March 10, 2009. Late tests will not be accepted. Donโt forget to
simplify all of your answers and attach your work!
1. Add:
x
x
2
4
8+
โ
2. Subtract:
10
1
2
6
โ
โ
+
x
x
)4(
810
โ
โ
xx
x )10)(2(
625
โ+
โ
xx
x
3. Find the vertices of the functions: 4. Graph the following function: f(x) = x2 + 6x + 3
a) f(x) = 2x2 โ 16x + 35
(4, 3)
b) f(x) = โ9.8(x โ 1.3)2 + 12.1
(1.3, 12.1)
5. Solve for x, if possible: 4x2 = 5x + 12 6. Graph the following function: f(x) = 2(x โ 2)2 โ 3
2.4664, -1.2164
Given f(x) = 6x โ 3 and g(x) = 2x + 5 , find the following.
7. (f โ g)(x) 8. (f โข g)(x) 9. (f โฆ g)(x) 10. (g โฆ g)(x)
4x โ 8 12x2 + 24x โ 15 12x + 27 4x + 15
11. The cost of producing โxโ DVDs can be described by the function C(x) = 1.5x + 6000. The revenue can be
described by the function R(x) = 12x. Assume that the number of DVDs produced and sold is the same.
a) What is the function that represents the profit? b) How many DVDs need to be sold to break even?
P(x) = 10.5x โ 6000 572 DVDs
x y
-5
-2
-4
-5
-3
-6
-2
-5
-1
-2
x y
0 5
1 -1
2 -3
3 -1
4 5
