2018 - JAMB Mathematics Past Questions and Answers - page 5

First, express the two numbers in the same unit.
To convert 495g to kg, divide it by 1000

  495g = \(\frac{495}{1000}\)

  = 0.495kg

  To express in percentage, 0.495 will be divided by 16.5 and then multiplied by 100

  % will be added to the answer \(\frac{0.4950}{16.5}\) x 100

  = 3%

2√3 - 4) ( 2√3 + 4)

  = 12 + 8√3 - 8√3 – 16

  = 12 – 16

  = -4

To find the gradient to the curve, we differentiate the equation of the curve with respect to x

  \(\frac{dy}{dx}\) 2x - 2

  The gradient of the curve is the same with that of the tangent.

  At point (2, 0) \(\frac{dy}{dx}\) = 2(2) - 2

  = 4 – 2 = 2

  The equation of the tangent is given by (y - y1) \(\frac{dy}{dx}\) (x – x1)

  At point (x1, y1) = (2, 0)

  y - 0 = 2(x - 2)

  y = 2x - 4

The minimum value is the lowest value of the curve on y axis which gives a value of -5.3

log\(_2\) 8 – log\(_3\) \(\frac{1}{9}\)

  = log \(_2\) 2\(^3\) – log\(_3\) 9\(^{-1}\)

  = log\(_2\) 2\(^3\) – log\(_3\) 3\(^{-2}\)

  Based on law of logarithm

  = 3 log\(_2\) 2 – (-2 log\(_3\) 3)

  But log\(_2\) 2 = 1,

  log\(_3\) 3 = 1

  So, = 3 + 2

  = 5

  The correct option is the third quadrant only where Tanθ is positive and Sinθ is negative

The total number of students is ∑ f = 3 + 4 + 5 + 6 + 7 + 6 + 5 + 4

  = 40

A = (p, q, r, t, u, v)

  B = (r, s, t, u)

  A U B = Elements in both A and B = (p, q, r, s, t, u, v)

  (A U B)1 = elements in the universal set E but not in (A U B)= (w, x, y, z)

  n(A U B) 1 = number of the elements in (A U B)1 = 4

Locus is the path traced at by a point which moves in accordance with a certain law. It is also the set of all possible position occupied by an object The path traced from all possible location of 4cm from a given point P form a circle of radius 4cm with centre P.

Sin(5x - 28) = Cos(3x - 50)………..i

  But Sinα = Cos(90 - α)

  So Sin(5x - 28) = Cos(90 - [5x - 28])

  Sin(5x - 28) = Cos(90 - 5x + 28)

  Sin(5x - 28) = Cos(118 - 5x)………ii

  Combining i and ii

  Cos(3x - 50) = Cos(118 - 5x)

  3x - 50 = 118 - 5x

  Collecting the like terms

  3x + 5x = 118 + 50

  8x = 168

  x = \(\frac{168}{8}\)

  x = 21\(^o\)

  Answer is B