Basically when you input angle value its taken in rads, so if you want to use degrees then you should use:

convert((1/2)*Pi, degrees)

@rlopez You are very correct and precise.

@ThU Yeah but that's not clean. It's a hack. Let me inform this to the technical support.

@Ramakrishnan 

Adding RETURN key will append further Maple input lines that are not intended, its not clean formatting. I will contact Maple technical support to see what they say.

@rlopez 

"Now, what does it mean to delete a row? "

To delete a row that was later thought to be a redundant for the application.

"Suppose it is the second row that is to be deleted. What function value takes the place of "b" on the interval [1,2)? I think that's the essential question."

No that is not the essential question, the question is simply that; if you want to delete a row or in other words edit your piecewise function. What would one do. Go back, bring the cursor to the specific row and select the row and delete it. That is the most intuitive process and should be the most basic step to perform to achieve the desired result.

" it is recognized that this row is not wanted. Control-z will undo the insertion of the row."

Not a thorough solution process for all situations. Execute the input and go back and delete a row and try re-executing it, it would throw an error. Why?? Because Maple doesnt understand that the user decided to undo a row.

@vv I have a further question on this since you mentioned about 1D Math Input.

I am currently reading Ian Thompson's book - Understanding Maple. Even he suggests to do 1D Math. Could you please explain if I have to stick with 1D math all the time, I just purchased Maple and am still new to it coming from a Mathematica background.

Isn't 2D math useful since its the more akin to how we write by hand and helps us easier to understand.

Please advise. Thanks.

@Mac Dude Please see the results of these integrals in Eqn 27 and 28 of the attached PDF link (integral table).

I am trying to get the same results as shown in that. I have evaluated these integrals in Mathematica and it matches to the ones as shown in the integral table.

Why is Maple different, I was trying to understand that.

@cbanks Thank you. I dint find this tiny advise that makes a huge difference in any of those tutorial videos on Maple portal.

@Mac Dude 

No I do not mean forward referencing. Suppose I evaluate a set of equations sequentially, and I decided to insert another equation before the last evaluated equation. How do I go about doing that? for example If I want to go back and type something before (7) i.e. to edit my document in real time, I can't do it ?

As for the 2nd questions, I just noticed that it is automatically into 2D input mode, so I have to manually jump back and forth to input TEXT. Thanks for clarifying that.