Search results

Let the ring be O. AOB is a Δ where ∠AOB = π/3 and ∠ABO = π/6 (since AO = l , BO = 2l and AB = √3l). The ∑vertical forces on A = 0 , so T = mg (1) where T is the tension in the string AO = tension in BO. The ∑ of vertical forces on B = 0, so Tsinπ/6 =...

You can do this with basic probaility: 1^st draw --> P(red) = 5/9 2^nd draw --> P(red) = 4/8 3^rd draw --> P(white) = 4/7 P(red, red, white) = (5.4.4)/(9.8.7) = 10/63

Number of unique plates = (26)³.(10)³ (3 options of 26 letters each and 3 options of 10 digits) Number of Plates with 3 letters same and 3 numerals the same = 26.10 =260 (since there are 26 letters that can be repeated thrice and 10 digits to be repeated thrice) The...

The angle that OP makes with the horizontal is defined by the postition (x,y) of the particle such that tanβ = y/x. The angle of the trajectory (with respect to the horizontal) depends on the velocities V_x and V_y such that tanβ = |V_y /V_x|...

Scary stuff.

Shit life.

Most people find 4U maths hard at the begining (or right through to the end :p). If you're getting decent marks, i.e. >50%, then try not to be too disheartened and think things through. It gets easier as you go. Do it if you enjoy it, otherwise there's not much point really.

Let the tension in the string be T and note that the lengths given create that basic triangle with angles 30, 60 and 90° ∑ vertical = 0 so Tcos60° = mg T = 2mg (1) ∑ horizontal = mrw² Tsin60° = mrw² mg√3 = mrw² from (1)...

Let the tension in the string be T. ∑ vertical forces = 0 , i.e. Tcos30° = mg , T = mg/cos30° = 200/√3 N *note: this is the same as 20 √3/3 kg wt ... fitz notation is retarded ∑ horizontal = mw²r Tsin30° = mw²r w =...

i) consider E and I as a single unit such that you are dealing with 6 individual units (instead of 7). There are 6! ways of arranging these units but 2 ways of arranging E and I between themselves so the answer becomes: 2 . 6! = 1440 ii) This is an annoying one to explain in full but the...

Only one person can drive so remove him from the equation and leave him in place. Of the 6 people that are left, 4 can sit in the front so when filling those places you multiply (4 x 3). Considering the back you then have 4 people who can sit in any order yielding 4!. Hence, combining this, the...

if you remove the two of them then there are ²³C₃ ways to choose three from the rest. With them included there are ²⁵C₃ ways. I'm still fairly poor at the perms/combs/binomial stuff but I think it'd be...

And then to 23rd... I blame the parallel decrease in morale. I reckon we can pull up from last year but that depends on how much our years decides to bludge from now up until the HSC.

My physics mark is unscaled but I do think the teachers could have marked a bit harder for some questions. Our physics trial was a bit weird. Apparently the main body of the exam and the multiple choice parts were bought from external sources (we can't take our exams home yet due to the time...

English Advanced: 88% Math Extension 1: 94% (2nd or 1st out of 84) Math Extension 2: 83% (1st out of 49) Chemistry: 83% (6th out of about 71) Physics: 96% (1st out of about 67) English Extension 1: 72% (pwned... I made a slight mistake in reading BOTH questions i.e. 3 texts instead of 4 and...

I have a pile that's been building up over the HSC: Homer - The Odyssey Kant - Critique of Pure Reason (I got a little bit into this but decided to let it wait) Satre - Being and Nothingness Aurelius - Meditations edit - I just saw a couple more :p Mark Twain - Roughing It James...

I think that one's given.

Are you sure there's not an x² term in there somewhere? 'Cause I keep turning up answers in terms of 'n' via straight integration. Maybe I've fallen out of practise with the recurrence stuff already but trying the substitutions (u = 1 - x) and (x = sin²θ ) I got...

Fight the power dude.

Maybe if you don't do work. If someone puts in the time, gets dux of their year and HD's in a number of competitions then this would indicate to me that they have the potential to perform well in the future. It doesn't show that they'll rank so high in year 12/uni etc, given that people don't...