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## #1 2012-09-07 12:33:21

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

### deductive and inductive reasoning

Need help in seeing if my answer is correct

1-Will every ray contain a line segment?  Why?  What kind of reasoning is this?

1-Yes every ray will contain a line segment because a ray has two points it starts with an end point then it goes beyond the other point,  and a line only needs two points to define it and it lies between them therefore every ray has two points to contain a line segment. The reasoning is deductive.

2. If I have a line segment, and another point not on the line segment, how many different geometric elements from Lesson 1 might I have?  What kind of reasoning did you use? (This question is worth 2 points.)

2. I can have four (without counting the line segment) geometric elements from lesson 1 line, Point, line, ray, angle, and plane. I used inductive reasoning.

Last edited by zee-f (2012-09-07 12:51:53)

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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## #2 2012-09-07 19:40:48

bob bundy
Moderator
Registered: 2010-06-20
Posts: 7,969

### Re: deductive and inductive reasoning

hi zee-f

Every time you work from axioms to make theorems you are reasoning deductively.

Question 1 looks good to me.

In question 2 I have doubts about some of the elements you have claimed.  What is your reasoning in each case?

Why is this 'inductive ?

see

http://en.wikipedia.org/wiki/Inductive_reasoning

Bob

ps.  What other Compuhigh courses are you 'signed up' for?

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #3 2012-09-08 01:28:19

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

### Re: deductive and inductive reasoning

Hi Bob Bundy,

#2- In lesson 1 in the beginning it said we are going to learn about these elements: Point, line, line segment, ray, angle, plane.

A line segment lies between two selected points therefore it makes a line because a line needs two points two define it. It makes a ray because a ray has two points with a single ended arrow over it. A line segment  has  points and it lies on points so then I have points. Counting the point that is not in the line segment with the two points from the line segment makes an angle, and plane because an angle is a union of two rays having the same endpoint and the point from the point that is not on the line segment to one point on the line segment makes a ray and to the second point from the line segment makes another point so both of the rays have the same end point which is the point that is not on the line segment. It makes a plane because a plain  needs a line and a point not lying on the line to be defined and we have that we have two points from the line segment that made a line and a point that is not on the line. I used deductive reasoning.

It is deductive  because I  recognize that I know some things about Line segments in general, and I then apply that knowledge back to the particular line segment.

I can take up to 8 courses a year am currently taking biology and geometry I finished English, PE, American government  and algebra.

Last edited by zee-f (2012-09-08 02:04:24)

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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## #4 2012-09-08 01:35:42

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

### Re: deductive and inductive reasoning

But I still have a doubt about #1 because it is talking about all rays and  in the lesson these examples were given

Tom: Tara, try one of these red peppers fresh from the garden
Tara: Thats yummy, are fresh garden vegetables always so good?

Tara is observing the properties of the vegetables she is eating, and wants to reach a conclusion about all fresh garden vegetables.  This is inductive reasoning.

Sue: Hey Sam, have some chocolate cake.
Sam: No thanks, I dont like chocolate.

In this case, Sam is aware of properties of chocolate in general, and concludes therefore that this particular instance of chocolate, the chocolate on the cake, will not be pleasurable.  This is an example of deductive reasoning:  knowledge of abstract rules is used to make conclusions about a concrete instance.

So doesn't the make number 1 inductive because I am concluding about all rays or would it be deductive because I am using knowledge I know to make conclusions but I am not talking about a specific example I am talking about all rays and the lesson mentioned that  When you use inductive reasoning, you generalize from specific examples and discover some kind of rule.When you use deductive reasoning, you may know something general, and use that information to predict something about something more concrete.

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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## #5 2012-09-08 09:33:47

zee-f
Member
Registered: 2011-05-12
Posts: 1,220

### Re: deductive and inductive reasoning

Hey I submitted My answers and they were correct

1. Will every ray contain a line segment? Why? What kind of reasoning is this?

1. Yes every ray will contain a line segment because a ray has two points it starts with an end point then it goes beyond the other point, and a line only needs two points to define it and it lies between them therefore every ray has two points to contain a line segment. The reasoning is deductive I am using general information and I am using that information to predict something about something more concrete.

2. If I have two lines, will they cross? Explain fully. What postulate helps me answer this question?

2- They can and can't cross. It depends on the kind of line I am talking about if the lines were intersecting lines they will cross because intersecting lines are lines that meet at a same point so they will cross. If I have parallel lines they will never cross because parallel lines never intersect because they always have the same distance apart they will never meet no matter how much you stretched them. Parallel postulate talks about parallel lines never crossing so it can help answer this question.

One, who adopts patience, will never be deprived of success though it may take a long time to reach him. Imam ali (as)<3

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## #6 2012-09-08 09:46:50

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: deductive and inductive reasoning

Hi;

2) Is cool with me. Is there a third situation?

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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