Recent content by SaHbEeWaH

Answer to Q1: Question 2 If y = 2x2ln(5x) then find d2y/dx2.

I can assure you, however, that no first principals will be examined in 2 unit yet alone 3 unit... first principals is extension 1 prelim work and so it can be (and has been) tested in hsc 2u never learn it, they just use the formulas

yeah they're using 3u method but it's basically the same thing using 2u is much simpler to look at P(at least one japanese) = 1 - P(no japanese) = 1 - (7/10 * 6/9 * 5/8 * 4/7) = 0.8333...

alright my bad

I assumed it -10m/s^2 If you assume g = 9.8 then in theory throwing the projectile up will never fall down and since the ball is always accelerating up at a faster rate than the second you shouldn't even get an answer... Velocity is a vector quantity and since gravity pulls objects down...

You're not trying to find the probability so you don't need to divide the answer by the total amount of possible combinations Taking 3 letters at random from 8 letters = 8P3 ...divide by 2! because of the recurring E 8C3/2! = 168 possible letter sequences

it's being fired vertically up so there are no angles involved projectile 1: consider vertical motion a = -10 v = -10t + c at t = 0, v = 49, so c = 49 v = -10t + 49 y = -5t^2 + 49t projectile 2: consider vertical motion a = -10 v = -10t + c at t = 2, v = 49 49 = -20 + c c =...

So these 4 (successive) events can happen in 5C1 x 8C1 x 10C3 x 14C2 different ways This is impossible.. choosing 7 from 23 is 23C7 without restrictions, so it cannot be higher than this. You have to take each possibility one at a time: 1 independent, 1 labor, 5 liberal 1 independent...

You are confusing this with the difference of two cubes. (a + b)³ = (a + b)(a² + 2ab + b²) = a³ + 3ba² + 3ab² + b³ to solve that try this: let m = x + 1 m³ - y³ = (m - y)(m² + my + y²) and substitute

you might want to retry that :)

http://www.artofproblemsolving.com/Forum/forums.html /kids from this forum beg to differ

if it's a tangent to the x and y axes, then the center of radius lies on the line y = x so let the center of the circle be (xc,xc) xc is the radius perpendicular distance between center and tangent (which is the radius) xc = |4xc + 3xc - 60| / 5 (equal radii) 5xc = |7xc - 60| 5xc = 7xc...

something like.. sin3x = -sinx sin3x = sin(-x) if sinθ = sinα then θ = nπ + (-1)nα 3x = nπ + (-1)n(-x) 3x - (-1)n(-x) = nπ 3x + (-1)nx = nπ x(3 + (-1)n) = nπ x = nπ/(3 + (-1)n) don't know if you can do that i just made it up

P(selects 2 caramel chocolates): 3/10 * 2/9 * 7/8 * 3C2 = 7/40 P(selects 3 caramel chocolates): 3/10 * 2/9 * 1/8 = 1/120 Therefore, P(selects at least 2 caramel) = 7/40 + 1/120 = 11/60 or ... P(selects no caramel chocolates): 7/10 * 6/9 * 5/8 = 7/24 P(selects 1 caramel chocolate)...

on a more serious note, yea they're both correct