LaTeX/C2/Equations/English

	Initial conditions	# Copy equations.tex into numbers.tex Both equations.tex and numbers.tex should be sized Both should be opened in Texworks Both should be at the first line equations.tex should be at the top, and numbers.tex should be below Compile numbers.tex and get numbers.pdf numbers.pdf should be sized numbers.pdf should be scrolled all the way to the top eqn-slides.pdf should be at the first slide All should be arranged, as recorded in the tutorial equations.tex should be directly below the slides file
	Texworks: Lucida	Grande, 22pt, 20px. Preview: 75%, 200dpi
	Opening slide	Welcome to this tutorial on writing equations using LaTeX My name is Kannan Moudgalya
	Learning objectives slide Down arrow Down arrow Down arrow	In this tutorial, we will learn how to create an equation in LaTeX How to write multiple equations How to align multiple equations and Why we should avoid the dollar mode and blank lines while writing equations
	System requirements slide	One may use any of Linux, Windows or the Mac operating system One needs LaTeX I shall use Texworks, although it is not required
	Prerequisites slide Press Down arrow Down arrow	What are the prerequisites? One needs to be familiar with spoken tutorials that introduce LaTeX Exposure to the recommended method of side-by-side learning This information is available at the Spoken Tutorial webpage
	Additional material slide Open in Texworks Back to slides file, press down arrow Press down arrow Press down arrow	I shall use equations.tex I have opened it in Texworks It is available as a code file along with this tutorial You need to have it to practise along with me If you don't have it, please download it from the Spoken Tutorial website
	Slide on Leslie Lamport’s book Web browser is opened	I will next call your attention to this standard textbook by Leslie Lamport I learnt my LaTeX from this book It is available for about Rs. 500 Let me show on the web browser where one can buy it
		Let us begin the tutorial
	Open equations.tex Open numbers.tex	Let us learn how to write equations using LaTeX I have already opened the file equations.tex in TeXworks. I have saved it as numbers.tex to use in this tutorial I will keep the file equations.tex intact, and not change it Let me open numbers.tex Please pause the tutorial, make this copy and open it Whenever you want to start afresh, you can make a new copy of equations.tex I recommend this method whenever a code file is given with ANY spoken tutorial
	Press the typeset key	Let us compile this file by pressing the typeset arrow at the top left hand corner You can see the pdf file on the right Let us look at the tex file, which begins with its usual commands I have chosen the width of the pdf file to be 8cm This is the only way I can show the entire file and also use a large font
	Change 7 to 15 Put back 7 Click amsmath line	You may want to increase it to a more reasonable value, such as 15cm But I will continue to use 8cm I am using the package amsmath
	Click the first align click u(t) line in tex click u(t) on slide Hover on \left and click \right	I write the first equation within the align star environment, as shown here You can see how it gets typeset in the pdf file On the left hand side of this equation, we have u(t) On the right hand side, I have produced big square brackets How did I do this? With “back slash left square” and “back slash right square” brackets as shown here
	Scroll the tex file up Click align* line Click the x_1 line Click on the eqn Click on matrix pdf Click on matrix tex Delete row 1 compile Click the pdf Undo the last command in tex	Similarly, I write a second equation using align star On the left hand side, we have the derivative of a vector We can see the pdf output here On the right hand side, we have a 3 by 3 matrix See the corresponding output Suppose we delete the first row in this matrix and compile We get a 2 by 3 matrix pdf output The first line is gone It is your responsibility to make the equations correct and consistent Let me put the row back Let me compile You can also add more rows, if necessary Similarly, you can change the columns too
	Put $ and compile	Recall that we used the $ mode to write formulae in another tutorial Here, align plays the role of the $ mode In fact, one should not put the dollar sign within the align environment Suppose we put the alpha symbol within $ signs and compile We get an error message about $ Press the cross symbol on the top left red box And abort the previous compilation Let us remove the $ signs Compile again, it works
	Below the line with alpha, leave a blank line Put %	Another common mistake is leaving blank lines in the align environment Let me leave an empty line and compile It gives an error message If you need this gap, put %, the comment character, in the first column Abort compilation Compile again - we see that it works Let us remove this line and compile
	Remove \end{align*} Remove \begin{align*} Put the text into \intertext{} Compile Put & sign before = Repeat in the 2nd eqn. Compile	Next, I want to align the two equations by the equal to sign For this, we need to put both equations inside one align star environment Remove the end align* command of the first equation Remove the begin align* command of the second equation Let us compile We see only one equation appearing The text in between the two equations appears as a large string The second equation does not even show up This is not what we wanted This problem is solved with the help of the intertext command Let us put the text in between braces Let us also put this command back slash intertext as I type now Note that intertext is one word, without a space in between Do not forget the back slash before intertext Also, do not forget the closing brace These are all common mistakes On compiling, we get this pdf file You see the equations right aligned I am not happy with it I want to align by the equal to sign Let us put the ampersand sign in front of the equal to sign of the first equation Let us do it on the second equation also If you have more equations to be aligned, do this for all of them On compiling, we see the two equations aligned by the equal to sign
		The equations are aligned even though there is text in between. Remember to use the intertext command whether you want the equations aligned or not
	Delete text lines Put \\ Compile Undo	What do we do if we don’t have text between equations? To understand this, let us delete the entire text between the two equations Note that we should not leave an empty line On compiling, we see both equations coming in the same line We didn’t tell LaTeX to start the second equation in the next line We solve this by putting two back slashes Let us compile, to get the correct pdf file Let us now undo and put the text in between two equations Let us compile once more
		This is where we will stop Let me go to the slides
	Summary slide Down arrow Down arrow	This page summarises what we learnt in this tutorial Please recall each of these commands This is your first assignment
	More assignments slide Down arrow	I will give some more assignments Can you pause the video and try to produce these equations? The required code is given here
	Assignment 3	Can you produce these equations? Notice that these equations are now aligned at the equal to sign
	Assignment 4	What happens if you forget a required ampersand sign? Please pause the video and try this input You should get this output Forgetting ampersand signs is a common mistake made by everyone!
	Assignment 5	Can you pause this video and try to produce this output? Use the hint given here
	Assignment 6	In this assignment, you have to align three equations Please pause the video here, and try to produce them by yourself I have given the answer here
	Assignment 7	I have the last assignment in this slide Insert some text between equations
	About the ST slide	I will now give some general information This video summarises the Spoken Tutorial project
	Workshops slide	We conduct workshops using Spoken Tutorials
	Answers slide Press down arrow Down arrow Down arrow Down arrow Down arrow twice	Do you have questions in THIS Spoken Tutorial? * Please visit this site Choose the minute and second where you have the question Explain your question briefly Someone from our team will answer them You will have to register on this website to ask questions
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	Acknowledgement slide	Spoken Tutorial project is funded by MHRD, Government of India
		Thanks for joining Goodbye

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Chandrika, Nancyvarkey, Pravin1389