Name: Key
Math 1090 - Preliminary Assignment
Simply complete this and hand it in the second day of class for full credit.
1. Evaluate
|x|
x
if x is a negative number.
Answer: Since x is negative, |x| = −x. That is, −x is positive. So,
|x|
−x
=
= −1.
x
x
2. Evaluate
3
4
+ 85 .
Answer:
3 5
6 5
11
3
+ = + =
or 1 .
4 8
8 8
8
8
3
Note that mixed numbers such as 1 8 can be confusing notationally, so we will not use them.
3
3. Evaluate 16 2 .
Answer:
3
2
16 = 16
1
·3
2
= 16
1
2
3
= 43 = 64.
4. Using the order of operations, evaluate 5 · (−8 + 62 ÷ 4).
Answer:
5 · (−8 + 62 ÷ 4) =
=
=
=
5(−8 + 36 ÷ 4)
5(−8 + 9)
5(1)
5.
6
5. Simplify by rationalizing the denominator. √3−1
Answer:
√
6
3+1
6
√
= √
·√
3−1
3−1
3+1
√
6 3+1
√
√
=
3+ 3− 3−1
√
6 3+1
=
← (Up to this point would be fine.)
√ 2
= 3
3+1
√
= 3 3 + 3.
1