Interesting solve by integrand. Is that legible in an exam? lol
I wouldn't accept this as a proper proof from scratch. Reason being that the meat of the problem is essentially circumvented by using the fact that the derivative of x^3 is 3x^2.I don't see why not. The only important thing to notice however is that he used both parametrics and inverse functions, which are parts of the 3U course. (Nonetheless, I haven't heard of 3U knowledge being prohibited in a 2U paper.)
What if you included the first-principles differentiation of first? I would have put it in my post, but it was done by someone else just two posts above.I wouldn't accept this as a proper proof from scratch. Reason being that the meat of the problem is essentially circumvented by using the fact that the derivative of x^3 is 3x^2.
Yep, then that would of course be a complete proof.What if you included the first-principles differentiation of first? I would have put it in my post, but it was done by someone else just two posts above.
To my best understanding, it doesn't matter who tries or solves the question. What matters is everyboday lets the ball rolling, ie, when one question is surely solved, post a new question! The students still have chance to try the question that is already solved because they don't have to read others' solution if they do want to have a go.Isn't the point of these marathon threads for HSC students to answer the questions, and for teachers to jump in only when there is an issue with the question, when a student has made an incorrect attempt at the question, or after a couple of days when no-one has been successful.
The higher Ext 2 thread is a bit different because the thinking involved is closer to uni level (and I have jumped in there after a couple of days), but I don't see the point of a teacher jumping in and answering one of these 2 unit questions only half a day after it was asked.
The function's value is 03 + 1 = 1 at x = 0.need help, i keep getting 9 but answer says 10
using 1 subinterval/use trapezoidal rule
hint:1. draw a diagram 2. with area no \pi
i did volume D: ceebshint:1. draw a diagram 2. with area no \pi
How did you do it?ln(4) +9