Integration: Just checking an answer

[Monkeyseat]

Hi, I think I've done this correct but the book says otherwise, please could someone check what I have done?

Question:

1) Find y in terms of x for each of the following (I've done question "a", "b", "c", "d" etc. just need to check question "j"):

My working:

Book's answer:

Just wondering who's right? If I'm wrong, please could you point out where I have gone wrong? I've checked over it and can't see any obvious mistakes that would lead to the wrong answer. I got all the other questions right in the section I think so it has led me to believe the book is wrong, but I just want to clarify.

Again sorry for posting it as pictures but I find it quicker/easier.

Many thanks guys.

 

[tkhunny]

Change your signature and simply quit being "rubbish".

I'm guessing the book has a typo - missing the negative sign. Why do you doubt?

 

[Monkeyseat]

Change your signature and simply quit being "rubbish".

I'm guessing the book has a typo - missing the negative sign. Why do you doubt?

It's easy to say that but I am getting better - I'm certainly better than I was a few years back obviously but I'm taking more in. Maths is not my favourite subject but I am trying hard but I am still learning, but as a result I ask a lot of questions others might think are obvious. Ok, I'm probably not "rubbish" compared to people doing the same A Level course as me, but I am definately rubbish compared to some people here hehe. I added that signature back in like 05 or something lol so it's a bit out of date, I'm hardly a regular member so I forgot about it but I've changed it now.

I didn't necessarily doubt my answer, I was just confirming whether the book was incorrect. It has many wrong answers and I don't know who is right sometimes. Also, I don't get the answers correct all the time and I've not been doing this topic for long so I thought I might have done something wrong, just thought I might as well check.

Thank you for the reply.