WAEC - Further Mathematics (2014)

1
If \(\frac{1}{5^{-y}} = 25(5^{4-2y})\), find the value of y.
Answer
(B)
2
2
Simplify: \((1 - \sin \theta)(1 + \sin \theta)\).
Answer
(D)
\(\cos^{2} \theta\)
3
Given that \(3x + 4y + 6 = 0\) and \(4x - by + 3 = 0\) are perpendicular, find the value of b.
Answer
(B)
3
4
Given that \(x * y = \frac{x + y}{2}, x \circ y = \frac{x^{2}}{y}\) and \((3 * b) \circ 48 = \frac{1}{3}\), find b, where b > 0.
Answer
(C)
5
5
If \(f(x) = 3x^{3} + 8x^{2} + 6x + k\) and \(f(2) = 1\), find the value of k.
Answer
(A)
-67
6
If \(8^{x} ÷ (\frac{1}{4})^{y} = 1\) and \(\log_{2}(x - 2y) = 1\), find the value of (x - y).
Answer
(A)
\(\frac{5}{4}\)
7
Simplify \(\frac{1 + \sqrt{8}}{3 - \sqrt{2}}\).
Answer
(D)
\(1 + \sqrt{2}\)
8
Using the binomial expansion \((1+x)^{6} = 1 + 6x + 15x^{2} + 20x^{3} + 15x^{4} + 6x^{5} + x^{6}\), find, correct to 3 dp, the value of \((1.98)^{6}\).
Answer
(C)
60.255
9
If \((x + 2)\) and \((3x - 1)\) are factors of \(6x^{3} + x^{2} - 19x + 6\), find the third factor.
Answer
(A)
\(2x - 3\)
10
If \(2, (k+1), 8,...\) form an exponential sequence (GP), find the values of k.
Answer
(D)
-5 and 3
11
A box contains 5 red and k blue balls. A ball is selected at random from the box. If the probability of selecting a blue ball is \(\frac{2}{3}\), find the value of k.
Answer
(D)
10
12
If \(\frac{x + P}{(x - 1)(x - 3)} = \frac{Q}{x - 1} + \frac{2}{x - 3}\), find the value of (P + Q).
Answer
(C)
0
13
Find the derivative of \(\sqrt[3]{(3x^{3} + 1}\) with respect to x.
Answer
(B)
\(\frac{3x^{2}}{\sqrt[3]{(3x^{3} + 1)^{2}}}\)
14
If \(T = \begin{pmatrix} -2 & -5 \\ 3 & 8 \end{pmatrix}\), find \(T^{-1}\), the inverse of T.
Answer
(A)
\(\begin{pmatrix} -8 & -5 \\ 3 & 2 \end{pmatrix}\)
15
A function is defined by \(h : x \to 2 - \frac{1}{2x - 3}, x \neq \frac{3}{2}\). Find \(h^-1\), the inverse of h.
Answer
(B)
\(\frac{3x - 7}{2x - 4}, x \neq 2\)
16
A function is defined by \(h : x \to 2 - \frac{1}{2x - 3}, x \neq \frac{3}{2}\). Find \(h^{-1}(\frac{1}{2})\).
Answer
(B)
\(\frac{11}{6}\)
17
The radius of a sphere is increasing at a rate \(3cm s^{-1}\). Find the rate of increase in the surface area, when the radius is 2cm. 
Answer
(D)
\(48\pi cm^{2}s^{-1}\)
18
Age in years 10 - 14 15 - 19 20 - 24 25 - 29 30 - 34
Frequency 6 8 14 10 12

What is the class mark of the median class?

Answer
(B)
22
19
Age in years 10 - 14 15 - 19 20 - 24 25 - 29 30 - 34
Frequency 6 8 14 10 12

 

In which group is the upper quartile?

Answer
(C)
25 - 29
20
Age in years 10 - 14 15 - 19 20 - 24 25 - 29 30 - 34
Frequency 6 8 14 10 12

Find the mean of the distribution.

Answer
(A)
23.4
21
If \(Px^{2} + (P+1)x + P = 0\) has equal roots, find the values of P.
Answer
(B)
\(\text{1 and }\frac{-1}{3}\)
22
Integrate \((x - \frac{1}{x})^{2}\) with respect to x.
Answer
(D)
\(\frac{x^3}{3} - 2x - \frac{1}{x} + c\)
23
Given that \(AB = \begin{pmatrix} 4 \\ 3 \end{pmatrix}\) and \(AC = \begin{pmatrix} 2 \\ -3 \end{pmatrix}\), find |BC|.
Answer
(C)
\(2\sqrt{10}\)
24
Find the angle between \((5i + 3j)\) and \((3i - 5j)\).
Answer
(B)
90°
25
Find the coefficient of \(x^3\) in the binomial expansion of \((3x + 4)^4\) in ascending powers of x.
Answer
(A)
432
26
If a fair coin is tossed four times, what is the probability of obtaining at least one head?
Answer
(D)
\(\frac{15}{16}\)
27
Forces 90N and 120N act in the directions 120° and 240° respectively. Find the resultant of these forces.
Answer
(D)
\(-15(7i + \sqrt{3}j)\)
28
The deviations from the mean of a set of numbers are \((k+3)^{2}, (k+7), -2, \text{k and (} k+2)^{2}\), where k is a constant. Find the value of k.
Answer
(D)
-3
29
Find the equation of a circle with centre (2, -3) and radius 2 units.
Answer
(A)
\(x^{2} + y^{2} - 4x + 6y + 9 = 0\)
30
The first term of a linear sequence is 9 and the common difference is 7. If the nth term is 380, find the value of n.
Answer
(B)
54
31
For what values of m is \(9y^{2} + my + 4\) a perfect square?
Answer
(D)
\(+12\)
32
A particle accelerates at 12\(ms^{-2}\) and travels a distance of 250m in 6 seconds. Find the initial velocity of the particle.
Answer
(A)
5.7\(ms^{-1}\)
33
In how many ways can 9 people be seated on a bench if only 3 places are available?
Answer
(B)
504
34
Find the variance of 1, 2, 0, -3, 5, -2, 4.
Answer
(A)
\(\frac{52}{7}\)
35
If the points (-1, t -1), (t, t - 3) and (t - 6, 3) lie on the same straight line, find the values of t.
Answer
(C)
t = 2 and 3