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qldbulls

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Got this in a 2 unit past paper, would I be awarded marks if I used a u-sub or do I have to do a advanced-syllabus method which I am completely stumped on someone please remind me

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scaryshark09

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Got this in a 2 unit past paper, would I be awarded marks if I used a u-sub or do I have to do a advanced-syllabus method which I am completely stumped on someone please remind me

View attachment 39770
just use adv method, using u-sub it too risky.
its a very simple question btw. cosx is the derivative, so integral is (sinx^3)/3
its just the chain rule i think its called
 

SadCeliac

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just use adv method, using u-sub it too risky.
its a very simple question btw. cosx is the derivative, so integral is (sinx^3)/3
its just the chain rule i think its called
chain rule is when you differentiate [f(x)]^n to get nf'(x)[f(x)]^n-1

reverse chain rule (which is what sharky meant) is when you do the opposite (ie. during integration)

Got this in a 2 unit past paper, would I be awarded marks if I used a u-sub or do I have to do a advanced-syllabus method which I am completely stumped on someone please remind me

View attachment 39770
basically you see that you have cosx which is the derivative of sinx

honestly you could use u-sub if it makes it clearer for yourself, I used to do it when I did 2u, but you don't get any extra marks --I assume that was a 2 marker??
 

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