Integration Question?? (1 Viewer)

[msaid]

literally in question 1 of a hsc paper, must not be seeing it?

 

[InteGrand]

View attachment 32558

literally in question 1 of a hsc paper, must not be seeing it?

 

[msaid]

Thanks, yeh it was fine using the substitution im just used to getting the substitution in 3u. Didn't really get the solution given in the successone book. Anyway thanks!

 

[InteGrand]

Thanks, yeh it was fine using the substitution im just used to getting the substitution in 3u. Didn't really get the solution given in the successone book. Anyway thanks!

I'm guessing they just did it by inspection (without a substitution)?

 

[photastic]

Don't really need a substitution if you actually explored the calculus of trigonometry.

 

[InteGrand]

The good old reverse chain rule (aka inspection).

 

[msaid]

hahahah tbh i feel like a bit of an idiot, is this something that's done in a bit more detail in 4u??
In the successone book they just used that formula^^. Of all the papers ive done i dont think ive come across that once but hey better now than in the exam

 

[Drsoccerball]

hahahah tbh i feel like a bit of an idiot, is this something that's done in a bit more detail in 4u??
In the successone book they just used that formula^^. Of all the papers ive done i dont think ive come across that once but hey better now than in the exam

Ive seen it a lot tbh. For example

 

[InteGrand]

 

[msaid]

Please correct me if im wrong but would that then equal [ln(x)^2]/2 ?? See now im feeling like ive just forgotten some simple integration

yeh just looking at that answer feels wrong

 

[InteGrand]

Please correct me if im wrong but would that then equal [ln(x)^2]/2 ?? See now im feeling like ive just forgotten some simple integration

yeh just looking at that answer feels wrong

Yeah that's correct.

 

[msaid]

Alright thanks for the help, ill now scavenge through HSC papers looking for this style of question