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    Stuck on an example. MIF 3.08 Example 26

    How/why do we get the line in the red box?
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    Cambridge 4I Q17 a) and c)

    The enrichment questions always make me feel inadequate. I can't figure out part a). b) is done 👍 .
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    Differentiation

    Just doing some practice on Khan Academy. I'm just wondering why the working out on the right is wrong. If I use dV/dt = dV/dh * dh/dt , it also gives a different wrong answer. Why are these methods wrong?
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    Cambrdige 4I Q15

    For Q15 e) . Part of the solution uses the fact that I>0 for all n (highlighted in green). How do we know this?
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    Cambridge 4D Q15

    Is there a special name for this technique? I was able to find a solution for a). But I'm not sure how to use this to solve integrals and I want to look into it.
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    2023 HSC Q13.a)

    I can find the solution if I use the method in the marking guidelines. However, why doesn't my method give the correct answer? i. is good. ii. is good. iii. is wrong.
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    Volume of Rotation Question. (Cambridge Ext 1, 12F Q20. )

    Q20. c) i: I got wrong, and I disagree with the working out of the solutions book. ii: I couldn't solve this, and I disagree with the working out of the solutions book. Just posting this here to see what you guys can do with it :) Probably an oversight by me; but nonetheless, your help is...
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    Differential Equation Query

    For my work below; the book provides 1+2e^(-x) as the answer. If I simply re-write the initial problem with -dx on the RHS, and y-1 in the denominator of LHS I will get the same answer. But why doesn't it work otherwise? Or it does and I can't see why? Where is my working out wrong? (mind...
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    Easy Integral Question

    Hi guys, I'm stuck on something trivial. letting x = (u-4)^2 I get to the correct solution in terms of u: 2u - 8ln|u| + c However, my confusion begins when changing the answer back to be in terms of x. Since x = (u-4)^2 , u = x^(1/2)+4 OR u =-x^(1/2)+4 So shouldn't there be two solutions in...
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    De Moivre and Euler question

    Anyone else find this topic very tedious and frustrating? Anyway, I’m tired and can’t find how to solve q11. d). Could anyone help out pls
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    Cambridge EXT 2 - Chapter 2 | Q+As

    Hi guys, I have a question from this chapter (Proof). Please help, if you can. And if you have questions of your own from this chapter of the cambridge book, pls post them here and I'll try help as well. 2A Q13. Following directly the explanation of the question, it is clear that we have a)...
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    Cambridge EXT 2 - Chapter 1 | Q+As

    Hi guys, I have a few questions about this chapter. Please help, if you can. And if you have questions of your own from this chapter of the cambridge book, pls post them here and I'll try help as well. My questions: 1F Q12.a) After drawing the graph and looking at the answers, it's clear that...
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