Math topic中文

Applications differentiation

apply differentiation to gradients, tangents and normals, connected rates of change and maxima and minima problems

Practice questions

  1. 1The diagram shows a greenhouse built on a rectangular base. 140 m2140\text{ m}^2 of polyethene is used to build the curved r…
  2. 2In the triangle ABCABC, AB=x cmAB = x\ \text{cm}, AC=3x cmAC = 3x\ \text{cm} and angle BAC=2π3BAC = \dfrac{2\pi}{3}. If xx is increasing…
  3. 3A curve has the equation y=2x−33x+4y = \frac{2x - 3}{3x + 4}, where x≠−43x \ne -\frac{4}{3}. The normal to the point PP on the cur…
  4. 4Find the gradient function of the curve y=2x2−ln⁡x+cy = 2x^2 - \ln x + c. The curve touches the positive xx-axis at point TT. Fi…
  5. 5The normal to the curve y=2tan⁡3x−1y = 2\tan 3x - 1 at point P(π3,−1)P\left(\frac{\pi}{3}, -1\right) crosses the yy-axis at point AA…
  6. 6The point PP lies on the curve y=ln⁡(x+1x−1)y = \ln\left(\frac{x+1}{x-1}\right) for x>1x > 1. The normal to the curve at PP is par…
  7. 7The radius of a circle increases at a rate of 3 cm s^{-1}. Find, in terms of π\pi, the rate of increase of the area whe…
  8. 8The figure shows part of the curve y=g(x)y = g(x). (2,8)(2, 8) and (6,1)(6, 1) are two points on the curve. Given that ∫26y dx=32\int_{2}^{6} y \text{ } dx = 32…
  9. 9The diagram shows part of the curve y=3e−12x−6y = 3e^{-\frac{1}{2}x} - 6 which crosses the xx-axis at PP and the yy-axis at QQ…
  10. 10The volume of liquid in a container, V m3V\ \text{m}^3, is given by V=0.05[(3x+2)3−8],V = 0.05\bigl[(3x+2)^3 - 8\bigr], where xx is the…
  11. 11已知函数f(x)=ex−1f(x)={{e}^{x}}-1,g(x)=sin⁡x(1)g(x)=\sin x(1)判断F(x)=f(x)−g(x)F(x)=f(x)-g(x)在x∈[0,+∞)x\in[0,+\infty)上零点的个数; (2)当x∈[0,π]x\in[0,\pi]时,f(x)⩾ag(x)(a∈R)f(x)\geqslant ag(x)(a\in R)…
  12. 12A motorist, travelling at a constant velocity of V m/s, passed a fixed point X and saw few vehicles ahead. He stepped on…
  13. 13A cone of height, hh and radius, rr fits exactly inside a sphere of radius 5 cm5\text{ cm} as shown below. (Volume of cone=13πr2h)\left(\text{Volume of cone} = \frac{1}{3}\pi r^2 h\right)…
  14. 14The diagram shows part of the curve y=3x+4y = \sqrt{3x + 4}. The line ABAB is tangent to the curve at AA. The points BB an…
  15. 15Given that y=45(x12−1)6y = \frac{4}{5}\left(\frac{x}{12} - 1\right)^6 and that both xx and yy vary with time, find the value of…
  16. 16The gradient function of a curve y=f(x)y = f(x) is given by 36(2x+1)2\frac{36}{(2x+1)^2} for x>−12x > -\frac{1}{2}. The curve passes t…
  17. 17It is given that y=4xsin⁡2xy = 4x \sin 2x. Show that dydx\frac{\mathrm{d}y}{\mathrm{d}x} can be expressed in the form axcos⁡2x+bsin⁡2xax \cos 2x + b \sin 2x…
  18. 18When the height of liquid in a container is hh m, the volume of liquid is V m3V\text{ m}^3 where V=0.06[(4h+1)3−7] and h≥0.25V = 0.06 \left[ (4h + 1)^3 - 7 \right] \text{ and } h \ge 0.25…
  19. 19A conical vessel, whose vertical angle is 30∘30^\circ as shown in the diagram, has water poured into it at such a rate th…
  20. 20The diagram shows part of the curve y=(1−x)(x−4)y = (1 - x)(x - 4) and two lines l1l_1 and l2l_2. The lines l1l_1 and l2l_2 are ta…
  21. 21Given the curve y=12e2x−13e−3x+13y = \frac{1}{2}e^{2x} - \frac{1}{3}e^{-3x} + \frac{1}{3} and the normal to the curve at point P(ln⁡2,5524)P\left(\ln 2, \frac{55}{24}\right)…
  22. 22The diagram shows the glass test tube of radius r cmr\text{ cm} and height (h+r) cm(h+r)\text{ cm} with a hemisphere of radius r cmr\text{ cm}…
  23. 23The diagram below shows the graph of y=12x+1y = \frac{1}{2x+1} and the tangent to the curve where the curve intersects the yy…
  24. 24ABCDABCD is a rectangle which fits inside a semicircle of radius 8 cm and centre OO. It is given that AB=xAB = x cm and BC=yBC = y…
  25. 25A farmer uses 160 m of fencing to enclose a plot of his land in a shape that comprises an isosceles triangle and a recta…
  26. 26The diagram shows part of the curve y=1(34x−5)2+1y = \frac{1}{\left(\frac{3}{4}x - 5\right)^2} + 1. PP is the point on the curve w…
  27. 27Oil is dripping into an empty inverted right circular cone at the rate of 16 cm3 per second. The height, h cm, of the co…
  28. 28A particle moves along the curve y=3(x+6)x+4y = \frac{3(x+6)}{x+4}, where x≠−4x \ne -4, in such a way that the yy-coordinate of th…
  29. 29A factory manufactures miniature containers that are made up of a closed circular cylinder and a hemisphere which have t…
  30. 30The point A lies on the curve y=xln⁡x2y = x \ln x^2, x>0x > 0. The tangent to the curve at A is parallel to the line y−3x=1y - 3x = 1…
  31. 31∀x∈(0,+∞)∀x\in(0,+∞),不等式xex−3−x−ln⁡x⩾axe^{x-3}-x-\ln x\geqslant a恒成立,则aa的最大值为()(\quad) A. −2-2 B. 00 C. e−2−1e^{-2}-1 D. −ln⁡3-\ln 3…
  32. 32[The volume of a sphere of radius r is 43πr3\dfrac{4}{3}\pi r^3, and its surface area is 4πr24\pi r^2.] The diagram shows a b…
  33. 33Air is being pumped into a spherical balloon at a constant rate of 12 cm3^3 per second. Find the rate at which the radi…
  34. 34The diagram shows part of the curve y=sin⁡xy = \sin x. A is a point on the curve that lies on the line x=π3x = \frac{\pi}{3}. T…
  35. 35The diagram shows part of the curve y=4−e−2xy = 4 - e^{-2x} which crosses the axes at AA and at BB. Find the coordinates of…
  36. 36A cone of height 12 cm and base radius 5 cm is placed over a cylinder of radius rr cm and height hh cm. The cone is in…
  37. 37The diagram shows part of the curve y=ex−1−2y = e^{x-1} - 2. The point P(2, e−2)P(2,\ e-2) lies on the curve and the normal to the cu…
  38. 38The gradient function of a curve is given by dydx=16x3−4\frac{\text{d}y}{\text{d}x} = \frac{16}{x^3} - 4. Given that the line 2y−x−6=02y - x - 6 = 0…
  39. 39[The volume of a cone of height hh and base radius rr is 13πr2h\frac{1}{3}\pi r^2 h.] A hollow right circular cone of base…
  40. 40The diagram shows a prism in which the cross-section is a trapezium ABCDABCD. AB=4x cmAB = 4x\text{ cm}, BC=DC=AD=2x cmBC = DC = AD = 2x\text{ cm}…
  41. 41A miniature model in the shape of a triangular prism is shown above. A piece of wire, 36 cm in length, runs through all…
  42. 42The diagram shows part of the curve y=4x+5y = \sqrt{4x + 5}. The normal of the curve at PP meets the xx-axis at TT. The xx…
  43. 43A curve is such that d2ydx2=6e3x−x\frac{d^2y}{dx^2} = 6e^{3x} - x and passes through the point (2,23e6)\left(2, \frac{2}{3}e^6\right). Gi…
  44. 44已知函数g(x)=1x⋅sin⁡θ+ln⁡x在[1,+∞)g(x)= \dfrac {1}{x\cdot \sin \theta }+\ln x{在}[1,+∞)上为增函数,且θ∈(0,π),f(x)=mx−m−1+2ex−ln⁡x,m∈Rθ∈(0,π),f(x)=mx- \dfrac {m-1+2e}{x}-\ln x,m∈R. (1…
  45. 45已知函数f(x)=x3+ax2+bx−a2−7af(x)=x^{3}+ax^{2}+bx-a^{2}-7a在x=1x=1处取得极大值1010,则ab\dfrac{a}{b}的值为()(\quad) A. −23-\dfrac{2}{3} B. −2-2…
  46. 46Baking powder is poured onto a flat surface at a constant rate of 2π cm3s−12\pi\text{ cm}^3\text{s}^{-1}, forming a right circu…
  47. 47The graph shows part of the curve y=−3(2x−4)−1/3y = -3(2x-4)^{-1/3}. The point P(−2, 1.5)P(-2,\ 1.5) lies on the curve and the normal to the…
  48. 48A gardener plans to construct two flower beds, one a circle of radius rr m, the other a square of side xx m. To protec…
  49. 49The diagram shows part of the curve y=2x+4y = \sqrt{2x + 4}, meeting the xx-axis at the point AA and the yy-axis at the p…
  50. 50The diagram shows part of the curve y=2sin⁡2x+1y = 2 \sin 2x + 1. PP is the maximum point of the curve and QQ is the point on t…
  51. 51Point PP lies on the curve y=kx22−xy = \frac{kx^2}{\sqrt{2-x}}, where kk is a constant. The xx-coordinate of PP is −2-2. G…
  52. 52The diagram shows part of the curve y=x3+3x2−2y = x^3 + 3x^2 - 2. The straight line LL cuts the curve at A(−3,−2)A(-3, -2), the x-axi…
  53. 53A capsule is made of a cylinder with a hemisphere at one end of the cylinder. The cylinder has a height, h cmh\text{ cm} a…
  54. 54The diagram shows a glass window ABCDEFABCDEF, consisting of a rectangle ABEFABEF of height 3x cm3x\text{ cm} and width y cmy\text{ cm}…
  55. 55Solutions to this question by accurate drawing will not be accepted. ABCDABCD is a trapezium where ADAD is parallel to…
  56. 56The diagram shows part of the curve y=14x2−12ln⁡(x3)y = \frac{1}{4}x^2 - \frac{1}{2}\ln\left(\frac{x}{3}\right) and P(3, 2.25)P(3,\,2.25) is…
  57. 57The function is defined by g(x)=x2−4x2+6g(x) = \frac{x^2 - 4}{x^2 + 6}, x>0x > 0. Explain, with working, whether g(x)g(x) is an increa…
  58. 58The diagram shows part of the curve y=27+8(x−2)3y = 27 + \frac{8}{(x-2)^3} which crosses the axes at points AA and BB. Explain w…
  59. 59The diagram shows part of the curve y=2sin⁡x2y = 2\sin\frac{x}{2}, where AA lies on the curve. The xx-coordinate of AA is 4π3\frac{4\pi}{3}…
  60. 60The diagram shows a paper weight which is made up of a solid hemisphere of radius rr cm, resting on top of a solid cyli…