Hey guys, I'm wondering which of those subjects to do for my second semester. I'm a first year doing Civil Engineering/Commerce. I was considering doing CHEM1011 since I've heard it's easier than MATS1101, but MATS1101 is the recommended elective so I'm not sure if I should. Also, instead of...
The sports uniform has been changed recently. A survey has been going around regarding changing the normal uniform, so there is a chance that it'll be revised before the school moves.
Re: HSC 2015 3U Marathon
In the second triangle tan(x/2)=t. Using this triangle, you can find sinx, cosx and tanx in terms of t. The first triangle is the sides of a triangle with sinx, cosx and tanx in terms of t.
So there's 13 ways of choosing 2 cards from a group of 4 cards with the same value. The 12C3 is then choosing 3 cards of different value from the 12 remaining card values that haven't been chosen. But why the 4³?
Re: HSC 2015 3U Marathon
\begin{align*}\textup{If we let }x&=e^{-2t} \textup{ we have:} \\S&=x+2x^2+3x^3+4x^4+... \\Sx&=x^2+2x^3+3x^4+4x^5+... \\S-Sx&=x+2x^2+3x^3+4x^4+...-x^2-2x^3-3x^4-4x^5-... \\S(1-x)&=x+x^2+x^3+x^4+... \\&=\frac{x}{1-x} \textup{ using }S_\infty=\frac{a}{1-r}...
Re: HSC 2015 3U Marathon
$I'm assuming you've got the first part done. For the projectile released at $O$: $x=Vt\cos{\alpha}$, $y=\frac{-gt^2}{2}+Vt\sin{\alpha}$. For the projectile released at $A$: $x=Ut\cos{\beta}$, $y=\frac{-gt^2}{2}+Ut\sin{\beta}+20$. When the particles collide at time $T$...
Re: HSC 2015 3U Marathon
Someone correct me if I'm wrong, but I think polynomials can not have negative indices. So since you know P(x)=0, you should times through by x3 at the end to leave only positive indices.