• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Search results

  1. D

    Mathematics: Post your doubts here!

    in the first part, use the triangle shown in the diagram. tan60 = r/h r = tan60 h put this in V = pi*r^2*h V = pih^3 dV/dh = 3pih^2 dV/dt = -k sqrt (h) dV/dt = dV/dh * dh/dt dh/dt = dV/dt / dV/dh dh/dt = - (k/3pi) * h^(2/5) in the second part, take h to the other side, integrate both sides and...
  2. D

    Mathematics: Post your doubts here!

    the blue angle is 135. both the blue lines have length 2. Use cosine rule to find the length of the green line. Edit: for a part let w = x + iy (x + iy) + 3(x-iy) = i(x+iy)^2 4x - 2iy = ix^2 - iy^2 - 2xy equate real and imaginary parts 4x = -2xy y = - 2 -2y = x^2 - y^2 put y = -2 x = sqrt 8
  3. D

    Mathematics: Post your doubts here!

    the distance we need to find has 2 components, the purple and red distances. If the purple distance is x then in triangle PQR (1 + x)^2 = 1^ + 1^ x = sqrt2 - 1 In the brown triangle, the hypotenuse is sqrt2 the red distance is half of this so the distance is (sqrt2 - 1) + sqrt2/2 = 1.12
  4. D

    Mathematics: Post your doubts here!

    It's above B for 2.4 seconds. It is going up for half of that time to reach the max height. For the other half, it's falling back down to B. I just considered the first half of the motion, when it starts from t = 0 and reaches the maximum height at 3 seconds. Since I considered only half of the...
  5. D

    Mathematics: Post your doubts here!

    Find the time to reach max height. u = 30 v = 0 a = -10 t = ? 0 = 30 - 10t t = 3 seconds It reached B at 3 - 2.4/2 = 1.8 s u = 30 a = -10 t = 1.8 s =? s = 30(1.8) +(0.5)(-10)(1.8)^2 s = 37.8 m
  6. D

    Mathematics: Post your doubts here!

    Triangle AOB is isosceles since OB = r. Use law of cosine in AOB and you'll get r^2 = AB^2 + r^2 - 2ABrCosθ Simplify and you'll get AB = 2rCosθ Angle AOB is (pi - 2θ) Shaded area = Area of sector BAC+2*Area of sector BOA−2*Area of triangle BOA put this equal to half of the area of the circle...
  7. D

    Mathematics: Post your doubts here!

    let the direction of the plane = n = (a,b,c) since the plane is perp. to the given plane, their direction vectors are perpendicular, so the dot products of their direction vectors is 0. (a,b,c) . (1,2,3) = 0 a + 2b + 3c = 0 Eq 1 since the plane is parallel to the line, n is perp. to the...
  8. D

    Mathematics: Post your doubts here!

    B will go up 0.36m because A has gone down 0.36m, but then it will move a small distance once A reaches the floor. So we need to find that distance. A's final velocity before reaching the ground is 1.2m/s, which is also the initial velocity of B when it starts to move the extra distance. u =...
  9. D

    Mathematics: Post your doubts here!

    Find the 2 angles in the triangle. There are 2 tension forces, one going towards A and the other towards C. By resolving forces at B, you can make 2 equations 8 = TaSin(53.13) + TcSin(36.87) TaCos(53.13) = TcCos(35.87) Solve simultaneously and you'll get Ta = 6.4 N ii) Resolve the forces at...
  10. D

    Mathematics: Post your doubts here!

    http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/Mathematics%20(9709)/9709_w06_qp_3.pdf Question 5 first part.
  11. D

    Mathematics Question

    Use integration by parts to find the integral of: ∫ ln(x) * 1 dx where u = ln(x) u' = 1/x dv = 1 v = x uv - ∫u'v = xln(x) - ∫(1/x) * x = xln(x) - x + C
  12. D

    Maths, Addmaths and Statistics: Post your doubts here!

    Volume of Prism: Base Area * Height Volume of pyramid: 1/3* base area * height.
  13. D

    Maths, Addmaths and Statistics: Post your doubts here!

    Add up all the numbers in the table or use the bar graph.
  14. D

    Maths, Addmaths and Statistics: Post your doubts here!

    Total cars = 48 Total number of cars belonging to 2-car families = 12 12/48 = 1/4
  15. D

    Maths, Addmaths and Statistics: Post your doubts here!

    Who's watching champion's league?
  16. D

    Maths, Addmaths and Statistics: Post your doubts here!

    When y = 0, x^3 = 5. So you just have to write down the value of x when y = 0. From the graph, it's 1.7.
  17. D

    Can a math genius appearing for 4024 solve this? :)

    You forgot the part where it says the temp. is -4C at 3000m a) 3000: 20 1800 : x x = 1800 * 20/3000 x = 12 The temperature fell by 12, so it's 4C b) 3000 : 20 x : 16 x = 2400m c) 3000: 20 X : Temp Fall 20(height) = 3000(t.fall) t.fall = 20(x)/3000 t.fall = x/150 Temp =...
  18. D

    Maths, Addmaths and Statistics: Post your doubts here!

    No, like others said, you can just figure it out through trial and error. The formula is just a more consistent method.
  19. D

    Maths, Addmaths and Statistics: Post your doubts here!

    xy = A + 2x xy -2x = A x(y-2) = A x + A/(y-2)
  20. D

    Maths, Addmaths and Statistics: Post your doubts here!

    https://sites.google.com/site/urbangeekclassroomsg/emath-classroom/number-sequences this might help, courtesy of flrnab.
Top