Assignment 1

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course MTH 158

001. `* 1

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Question: * R.1.26 \ was R.1.14 (was R.1.6) Of the numbers in the set {-sqrt(2), pi + sqrt(2), 1 / 2 + 10.3} which are counting numbers, which are rational numbers, which are irrational numbers and which are real numbers?

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Your solution:

There are no counting numbers or integers, however 1/2+10.3 is an example of a rational number and -sqrt(2) and pi +sqrt(2) are both examples of irrational numbers

confidence rating #$&*:3 OK

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Given Solution:

* * ** Counting numbers are the numbers 1, 2, 3, .... . None of the given numbers are counting numbers

Rational numbers are numbers which can be expressed as the ratio of two integers. 1/2+10.3 are rational numbers.

Irrational numbers are numbers which can be expressed as the ratio of two integers. {-sqrt(2)}, pi+sqrt(2) are irrational numbers.. **

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Self-critique (if necessary): OK

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Self-critique Rating:3

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Question: * R.1.44 \ 32 (was R.1.24) Write in symbols: The product of 2 and x is the product of 4 and 6

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Your solution:

The product of 2 and x is the product of 4 and 6 would come out to mean that 2*x=4*6

confidence rating #$&*:3 OK

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Given Solution:

* * ** The product of 2 and x is 2 * x and the product of 4 and 6 is 4 * 6. To say that these are identical is to say that 2*x=4*6. **

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Self-critique (if necessary): OK

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Self-critique Rating:3

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Question:

* R.1.62 \ 50 (was R.1.42) Explain how you evaluate the expression 2 - 5 * 4 - [ 6 * ( 3 - 4) ]

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Your solution:

To evaluate we would first take what is in the parentheses (3-4) which would give us 2-5*4-{6*-1}. then do whats left in the parentheses which gives us 2-5*4+6. Then we use multiplication to give us 2-20+6. then add to get 2-26 and finally subtract giving us an answer of -12

confidence rating #$&*:3 OK

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Given Solution:

* * **Starting with

2-5*4-[6*(3-4)]. First you evaluate the innermost group to get

2-5*4-[6*-1] . Then multiply inside brackets to get

2-5*4+6. Then do the multiplication to get

2-20+6. Then add and subtract in order, obtaining

-12. **

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Question: * R.1.98 \ 80 (was R.1.72) Explain how you use the distributive property to remove the parentheses from the express (x-2)(x-4).

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Your solution:

Using the distributive property we would get x(x-4)-2(x-2), then again we use the distributive property to get x^2-4x-(2x-8). Once we simplify we would end up with x^2-6x+8.

confidence rating #$&*:3 OK

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Given Solution:

* * ** COMMON ERROR: Using FOIL. FOIL is not the Distributive Law. FOIL works for binomial expressions. FOIL follows from the distributive law but is of extremely limited usefulness and the instructor does not recommend relying on FOIL.

Starting with

(x-2)(x-4) ; one application of the Distributive Property gives you

x(x-4) - 2(x-4) . Applying the property to both of the other terms we get

x^2 - 4x - (2x -8). Simplifying:

x^2 - 4x - 2x + 8 or

x^2 - 6x + 8. *

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Self-critique (if necessary):OK

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Self-critique Rating:3

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Question:

* R.1.102 \ 86 (was R.1.78) Explain why (4+3) / (2+5) is not equal to 4/2 + 3/5.

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Your solution:

Well (4+3)/(2+5) would give us an answer of 7/7 or 1, while (4/2)+(3/5) would give us an answer of 2 3/5

confidence rating #$&*:3 OK

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Given Solution:

* * ** Good answer but at an even more fundamental level it comes down to order of operations:

(4+3)/(2+5) means

7/7 which is equal to

1.

By order of operations, in which multiplications and divisions precede additions and subtractions,

4/2+3/5 means

(4/2) + (3/5), which gives us

2+3/5 = 2 3/5

* Add comments on any surprises or insights you experienced as a result of this assignment.

"

Self-critique (if necessary):

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Self-critique rating:

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Question:

* R.1.102 \ 86 (was R.1.78) Explain why (4+3) / (2+5) is not equal to 4/2 + 3/5.

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Your solution:

Well (4+3)/(2+5) would give us an answer of 7/7 or 1, while (4/2)+(3/5) would give us an answer of 2 3/5

confidence rating #$&*:3 OK

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Given Solution:

* * ** Good answer but at an even more fundamental level it comes down to order of operations:

(4+3)/(2+5) means

7/7 which is equal to

1.

By order of operations, in which multiplications and divisions precede additions and subtractions,

4/2+3/5 means

(4/2) + (3/5), which gives us

2+3/5 = 2 3/5

* Add comments on any surprises or insights you experienced as a result of this assignment.

"

Self-critique (if necessary):

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Self-critique rating:

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&#Good responses. Let me know if you have questions. &#