Search results

I thought something wasnt right with my working since the question never mentioned anything about <b>equal</b> and opposite roots...

Maybe I shouldve used different pronumerals :) Ax^2 + Bx + C = 0 B^2 - 4AC > 0 but the equation is x^2+2bx+3c=0 so A = 1, B = 2b and C = 3c :. -4AC = -4*1*3c = -12c

This is what I was thinking. Since its a quadractic (:. only 2 roots) you have to make the sum of the roots (-b/a) = 0 So.... -2b = 0 :. b = 0 is one condition. Because b^2 - 4ac has to be greater than 0 for real roots and b = 0 then -4ac (-12c) has to be greater than zero. :. c < 0 Edit...

Sacred Heart Cabramatta :D

fixed the typo for that question (tends to happen when your doing it in your head) And sorry, I didnt read your entire method. :)

1. Prove that (1/(sinXcosX)) tan X = cot X (1/(sinXcosX)) sin^2x/sinxcosx = (1 -sin^2x) /sinxcosx = cos^2x/sinxcosx = cosx/sinx = cotx 2. Show that (6,-4), (5,-1) and (2,8) are collinear The equation of the line passing through (6,-4), (5,-1) is (y+1)/(x-5) = (-4+1)/(6-5)...

*jumps on the 4u bandwagon* neither :p Apart from question 6/7 which may make you scratch your head for a minute or so,n the rest of the test is pretty easy and time should NOT even be an issue!

t₁ = a = 43 t₈ = a + 7d = -6 Subbing t₁ into t₈ we get 7d = -49, so d = -7 Now that you know the commone difference just keep adding that to 43 to get your other terms 43, 43 + (-7), 43 + (2*-7)...

http://outreach.atnf.csiro.au/education/senior/astrophysics This is a fairly new site (a few days old I think) which although still in development, will soon have some pretty useful information for the astrophysics topic. Seeing as though his advertising it, I'm pretty sure its written by...

It varies from week to week for me. I remember at the beginning of year 12 I'd be doing all my homework as soon as I get home but now, I just take a nap :D Aside from a couple of maths questions, I really couldnt give a stuff namely because I dont need to put in 100% to get the UAI I want. If...

What do you mean? 2 hours is fine for the extension 1 exam (its only one extra unit).

DU MA! :D Fobs are funny as hell though (to laugh at that is). Its not the fact that they speak viet, but rather their attitude. Most act all hard and swear as if there was no tomorrow.

Physics and SOR I on the 3rd of november :D

Best in sefton aye... :D :p Watch out for pats this year (even though were comprehensive) Same here... after the half yearly exams I'm no longer outright first for phys and chem :(

Sorry, my mistake. I did read it incorrectly (damn parentheses :o ). The process is the same though. Just change it to suit the question and you should be fine.

let u = 2x² :. du/dx = 4x :.dx = du/4x int x((e^2x²) - 1) dx wherever you see 2x² put "u" and wherever you see dx put "du/4x" = int x(e^u -1)*du/4x = int [1/4][e^u - 1] du = [1/4] int e^u - 1 du =...

Im trying to think of a 2unit method but in the meantime... int [(x²)(e^2x² - 1)] / x dx = int x((e^2x²) - 1) dx let u = 2x² :. du/dx = 4x int x((e^2x²) - 1) dx = [1/4] int e^u - 1 du =...

4 subintervals = 5 function values

hmm... well heres the working

I did it.. but I dont agree with the answer I got. My "approximation" was equal to the exact area received through direct integration (pi²/4). Either I made a mistake (very likely) or I mustve used a hell of a lot of intervals :p