This is a frequent reason to why I am getting a number of questions wrong. It seems that my answer is not the same as the one on the mark scheme since I am going down a different path to them in order to simplify the questions to such a point that they are able to be integrated. However, I do think I am breaking the laws of maths which would be the cause of a wrong answer can someone please help and explain what I’ve done wrong here as although it’s a different route to the mark scheme I don’t see why it’s incorrect. Thanks in advance!!
This is a frequent reason to why I am getting a number of questions wrong. It seems that my answer is not the same as the one on the mark scheme since I am going down a different path to them in order to simplify the questions to such a point that they are able to be integrated. However, I do think I am breaking the laws of maths which would be the cause of a wrong answer can someone please help and explain what I’ve done wrong here as although it’s a different route to the mark scheme I don’t see why it’s incorrect. Thanks in advance!!
Yeah I did, I think that’s my problem it equals sin y doesn’t it.
No.
cosecycosy=cosy÷siny1=cosy×siny=cosysiny
You can integrate cosysiny by using recognition or a sin/cos subsitution or by using the sin2A identity.
Also, I'm not sure how you got 2cos2x on the other side of the equation. You need to be careful when simplifying trig fractions - it often makes things easier if you write the fraction out using the ÷ sign like I did above.