3 Subtraction rules – order matters

It’s important to remember that subtraction has different rules from addition.

For example, when you add up numbers, it doesn’t matter what order you add them up in. So 6 + 4 is exactly the same as 4 + 6. The result is 10 in both cases.

But in subtraction, order matters. So 6 – 4 is different from 4 – 6.

With the first, you start with 6, subtract 4, and are left with 2.

But with the second you start with 4 and if you subtract 6, which is a bigger number, you a
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How to Use the Quadratic Formula to Solve Algebraic Equations 
Using the quadratic formula to solve equations may bring one, two, or no algebraic solutions. The quadratic formula is special to quadratic equations. Run time 03:24.
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Lesson 03 - One Minute Romanian
In lesson 3 of One Minute Romanian you will learn to say that you can speak a little Romanian. Remember - even a few phrases of a language can help you make friends and enjoy travel more. Find out more about One Minute Romanian at our website - http://www.oneminutelanguages.com. One Minute Romanian is brought to you by the Radio Lingua Network and is ©Copyright 2008.Author(s): No creator set

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8.3.1 Fluorine-based etching of silicon

Given the noxious chemistry needed to etch silicon with a liquid, it is perhaps surprising that a gas can do the job at all. However, both xenon fluoride (XeF2) and chlorine trifluoride (ClF3) gases have been used successfully for just this purpose. Each acts as a source of fluorine atoms, which are just barely bound together into molecules and are easily rearranged around silicon atoms with which they form strong bonds, turning them into inert SiF4 gas. These
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WikiHow : Verzameling van stappenplannen
wikihow.jpg

Hier vind je tientallen stap-voor-stapinstructies voor alledaagse (en niet-alledaagse) bezigheden, ondersteund door afbeeldingen of filmpjes.

Van tomaten kweken tot naaien, van een cadeau inpakken tot een jongen zoenen.

Je kan zoeken via een …


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Newton's Universal Law of Gravitation Introduction (The Big G Equation)
Understanding Newton’s Universal Law of Gravitation. Including a dramatization of The Cavendish Experiment and force visualization via qualitative examples. Want Lecture Notes? This is an AP Physics 1 topic.

Content Times:
0:11 Reviewing the standard Force of Gravity or Weight equation
0:56 Newton’s Universal Law of Gravitation
1:48 Defining r
2:47 The Cavendish Experiment

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8.591J Systems Biology (MIT)
This course introduces the mathematical modeling techniques needed to address key questions in modern biology. An overview of modeling techniques in molecular biology and genetics, cell biology and developmental biology is covered. Key experiments that validate mathematical models are also discussed, as well as molecular, cellular, and developmental systems biology, bacterial chemotaxis, genetic oscillators, control theory and genetic networks, and gradient sensing systems. Additional specific t
Author(s): van Oudenaarden, Alexander

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2.5 Measuring capacity

The basic metric unit for capacity is the litre, usually denoted by the symbol l (though sometimes an uppercase L is used to avoid confusion with the number 1).

In the SI system, units such as cubic metres (m3), cubic centimetres (cm3) and cubic millimetres (mm3) are used. These two systems are linked because:

1 ml = 1 cm3

The animation below i
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3 Key skills assessment courses

This section gives advice and guidance to help you compile and present a portfolio of selected work. You are strongly advised to read through this section so that you have an idea of what is expected.

The key skills assessment courses provide an opportunity for you to integrate your development of key skills with your work or study. You may choose to concentrate on skills that you need to develop and improve for your job, for a new course, or personally to help you keep abreast of new d
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Professor Denis Noble, who was a pioneer in the field of systems biology building the first working mathematical model of the heart and has been given an honorary degree at Warwick, talks about how the future study of biology will change in the 21st Century.
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6.3 Planning stages

Having discussed the reasons to plan writing and the impact planning may have, now we need to look at planning itself and its two stages.


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Beyond Ebola: What’s Needed to Combat the Next Outbreak
A sustainable, long-term health care infrastructure is required to deal with outbreaks like the deadly Ebola virus in West Africa, says Wharton's Ezekiel J. Emanuel.
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TALAT Lecture 1601: Process modelling applied to age hardening aluminium alloys
This lecture describes the methodology for physical modelling of materials problems, with particular emphasis on heat treatment and welding of age hardening alloys materials; it establishes mathematical relations between different process variables (e.g. alloy composition, heat treatment procedure, welding conditions) and the alloy strength or hardness, based on sound physical principles (e.g. thermodynamics, kinetic theory, dislocation mechanics); it motivates faster process development, optimi
Author(s): TALAT,Ø Grong, The Norwegian Institute of Technol

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Pay Attention to the Penguins
Think of penguins as ocean sentinels, says Dee Boersma -- they're on the frontlines of sea change. Sharing stories of penguin life and culture, she suggests that we start listening to what penguins are telling us. Dee Boersma considers penguins ocean sentinels, helping us understand the effects of pollution, overfishing and climate change on the marine environment. Run time 15:09.
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References

Adams, B., Breazeal, C., Brooks, R. and Scassellati, B. (2000) ‘Humanoid robots: a new kind of tool’, IEEE Intelligent Systems, 15, 25–31.
Block, N. (1995) ‘On a confusion about a function of consciousness’, Behavioral and Brain Sciences, 18, 227–47.
Block, N., Flanagan, O. and Güzeldere, G. (eds) (1997), The Nature of Consciousness: Philosophical
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Radio Lingua Network News: 5 September 2008
The latest news from Radio Lingua including details of Coffee Break Spanish arrangements, new podcasts launched this autumn and the Radio Lingua video contest in which you can win an iPod.
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3.7 Systems methodologies for managing change

The use of systems concepts and models forms part of a process of investigation that is often described in the literature of systems, design and decision-making as a ‘methodology’, where a methodology is a process of enquiry, not a method to produce a predetermined result.

A systems methodology has the following characteristics.

  • It is, or it provides, the means for the investigator to draw up a plan for studying a situation. This encourages
    Author(s): The Open University

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בדיקה

Video link (see supported sites below). Please use the original link, not the shortcut, e.g. www.youtube.com/watch?v=abcde

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SP.2H3 Ancient Philosophy and Mathematics (MIT)
Western philosophy and theoretical mathematics were born together, and the cross-fertilization of ideas in the two disciplines was continuously acknowledged throughout antiquity. In this course, we read works of ancient Greek philosophy and mathematics, and investigate the way in which ideas of definition, reason, argument and proof, rationality and irrationality, number, quality and quantity, truth, and even the idea of an idea were shaped by the interplay of philosophic and mathematical inquir
Author(s): Perlman, Lee

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Glossary

Open glossary now...


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