How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.
The angles of a polygon are given by x, 2x, 3x, 4x and 5x respectively. Find the value of x.
24o
30o
33o
36o
Correct answer is D
Since there are 5 angles given, the polygon is a pentagon.
Sum of interior angles of a pentagon = (2(5) - 4) x 90° = 540°
\(\therefore\) x + 2x + 3x + 4x + 5x = 15x
15x = 540°
\(x = \frac{540}{15} = 36°\)
Given that I3 is a unit matrix of order 3, find |I3|
-1
0
1
2
Correct answer is C
Recall that a unit matrice is a diagonal matrix in which the elements in the leading diagonal is unity. Therefore,
I3 = \(\begin{pmatrix} 1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1 \end{pmatrix}\)
I3 = \(+1\begin{vmatrix} 1 & 0 \\ 0 & 1 \end{vmatrix} - 0\begin{vmatrix} 0 & 0 \\ 0 & 1 \end{vmatrix} + 0 \begin{vmatrix} 0 & 1 \\ 0 & 0 \end{vmatrix} \)
I3 = +1(1 - 0) - 0(0 - 0) + 0(0 - 0)
= 1(1)
= 1
3
4
5
7
Correct answer is C
\(\begin{vmatrix} 5 & 3 \\ x & 2 \end{vmatrix}\) = \(\begin{vmatrix} 3 & 5 \\ 4 & 5 \end{vmatrix}\)
10 - 3x = 15 - 20
-3x = 15 - 20 - 10
-3x = -15
x = 5
\(-\frac{4}{5}\)
\(-\frac{2}{5}\)
4
5
Correct answer is A
m * n = \(\frac{mn}{2}\)
Identify, e = 2
Let a \(\in\) R, then
a * a\(^{-1}\) = e
a * a\(^{-1}\) = 2
-5 * a\(^{-1}\) = 2
\(\frac{-5 \times a^{-1}}{2} = 2\)
\(a^{-1} = \frac{2 \times 2}{-5}\)
\(a^{-1} = -\frac{4}{5}\)
11
13
15
22
Correct answer is B
p * q = pq + p - q First execute for 3 * 4 ==> 3(4) + 3 - 4 = 12 + 3 - 4 = 11 Now we execute for 2 * 11 ==> 2(11) + 2 - 11 = 22 + 2 - 11 = 13