Year : 
1982
Title : 
Mathematics (Core)
Exam : 
JAMB Exam

Paper 1 | Objectives

1 - 10 of 48 Questions

# Question Ans
1.

Rationalize the expression \(\frac{1}{\sqrt{2} + \sqrt{5}}\)

A. \(\frac{1}{3}\)(\(\sqrt{5} - \sqrt{2}\)

B. \(\frac{\sqrt{2}}{3}\) + \(\frac{\sqrt{5}}{5}\)

C. \(\sqrt{2} - \sqrt{5}\)

D. 5(\(\sqrt{2} - \sqrt{5}\)

E. \(\frac{1}{3}\)(\(\sqrt{2} - \sqrt{5}\)

Detailed Solution

\(\frac{1}{\sqrt{2} + \sqrt{5}}\)
\(\frac{1}{\sqrt{2} + \sqrt{5}} \times \frac{(\sqrt{2} - \sqrt{5})}{(\sqrt{2} - \sqrt{5})}\)
= \(\frac{\sqrt{2} - \sqrt{5}}{2 - 5}\)
= \(\frac{\sqrt{2} - \sqrt{5}}{-3}\)
= \(\frac{1}{3} (\sqrt{5} - \sqrt{2})\)
2.

Simplify 3 - 2 \(\div\) \(\frac{4}{5}\) + \(\frac{1}{2}\)

A. 1\(\frac{3}{4}\)

B. -1

C. 1\(\frac{3}{10}\)

D. 1

E. 1\(\frac{9}{10}\)

Detailed Solution

3 - 2 \(\div\) (\(\frac{4}{5}\)) + \(\frac{1}{2}\)

3 - (2 x \(\frac{5}{4}\)) + \(\frac{1}{2}\) = 3 - \(\frac{10}{4}\) + \(\frac{1}{2}\)

= 3 - \(\frac{5}{2}\) + \(\frac{1}{2}\)

= \(\frac{6 - 5 + 1}{2}\)

= \(\frac{2}{2}\)

= 1
3.

If N560.70 is shared in the ratio 7 : 2 : 1, what is the smallest share?

A. N392.49

B. N56.70

C. N113.40

D. N112.14

E. N56.07

Detailed Solution

7 + 2 + 1 = 10

\(\frac{1}{10}\) x 560.70

= N56.07
4.

Seven years ago, the age of a father was three times that of his son, but in six years time the age of the son will be half that of his father, representing the present ages of the father and son by x and y, respectively, the two equations relating x and y are

A. 3y - x = 0; 2y - x = 0

B. 3y - x = 14; x - 2y = 6

C. 3y - x =7; x - 2y = 6

D. 3y - x = 14; y - 2x = 6

E. x + 3y = 7; x = 2y = 12

Detailed Solution

7 years ago, Father(x - 7) years old, Son (y - 7) years

x - 7 = 3(y - 7)
x - 7 = 3y - 21
3y - x = -7 + 21 = 14
3y - x = 14 ... (1)
In six years time,
x + 6 = 2(y + 6)
x + 6 = 2y + 12
2y + 12 = x + 6
12 - 6 = x - 2y
6 = x - 2y ... (2)
5.

The factors of 6x - 5 - x2 are

A. -(x + 3)(x + 2)

B. (x + 5)(x + 1)

C. (x - 5)(1 - x)

D. (x + 1)(x + 5)

Detailed Solution

6x - 5 - x2 = (-1)(-x2 - 5 + 6x)

= x2 - 6x + 5

= (x - 5)(x - 1)

-(x - 1) = 1 - x

= (x - 5)(1 - x)
6.

The solution of the quadratic equation bx2 + cx + a = 0 is given by

A. x = b \(\pm\) \(\frac{\sqrt{b^2 - 4ac}}{2a}\)

B. x = c \(\pm\) \(\frac{\sqrt{b^2 - 4ab}}{2b}\)

C. x = -c \(\pm\) \(\frac{\sqrt{c^2 - 4ab}}{2b}\)

D. x = -b \(\pm\) \(\frac{\sqrt{b^2 - 4ac}}{2b}\)

Detailed Solution

bx2 + cx + a = 0

a = b; b = c; c = a

x = -b \(\pm\) \(\frac{\sqrt{b^2 - 4ac}}{2a}\)

x = -c \(\pm\) \(\frac{\sqrt{c^2 - 4ab}}{2b}\)
7.

The graphical method of solving the equation x3 + 3x2 + 4x - 28 = 0 is by drawing the graphs of the curves

A. y = x3 and y = 3x2 + x - 28

B. y = x3 + 3x2 + 4x + 4 and the line y = \(\frac{28}{x}\)

C. y = x3 + 3x2 + 4x and y

D. y = x2 + 3x + 4 and y = \(\frac{28}{x}\)

E. y = x2 + 3x + 4 and line y = 28x

Detailed Solution

The graphical method of solving the equation x3 + 3x2 + 4x - 28 = 0 is by drawing the graphs of the curves

y = x2 + 3x + 4 and y = \(\frac{28}{x}\)`.
8.

Write the equation 2 log2x - x log2(1 + y) = 3 in a form not involving logarithms

A. 2x(1 + y) = 3

B. 2x - x(1 + y) = 8

C. x2 = 8(1 + y)x

D. x2 - x(1 + y) = 8

E. x2 - (1 + y)2 = 8

Detailed Solution

2log2 x - x log2 (1 + y) = 3

log2 \(\frac{x^2}{(1 + y)^x}\) = 3

= \(\frac{x^2}{(1 + y)^x}\)

= 23

= 8

= x2 = 8(1 + y)x
9.

Find \(\alpha\) and \(\beta\) such that x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x (\(\frac{y^{\frac{9}{7}}}{x^{\frac{45}{8}}}\))\(\frac{1}{9}\) = \(\frac{y^{\alpha}}{y^{\beta}}\)

A. \(\alpha\) = 1, \(\beta\) = \(\frac{5}{7}\)

B. \(\alpha\)= 1, \(\beta\) = -\(\frac{5}{7}\)

C. \(\alpha\)= \(\frac{3}{5}\), \(\beta\) = -6

D. \(\alpha\)= 1, \(\beta\) = -\(\frac{3}{5}\)

Detailed Solution

x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x (\(\frac{y^{\frac{9}{7}}}{x^{\frac{45}{8}}}\))\(\frac{1}{9}\) = \(\frac{y^{\alpha}}{y^{\beta}}\)

x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x y\(\frac{1}{7}\) = x\(\alpha\)

= x\(\frac{3}{8}\) + \(\frac{5}{8}\) + y\(\frac{6}{7}\) + \(\frac{1}{7}\)

= x\(\alpha\)y\(\beta\)

x1y\(\frac{-5}{7}\) = x\(\alpha\)y\(\beta\)

\(\alpha\) = 1, \(\beta\) = \(\frac{5}{7}\)
10.

Which of the following lines is not parallel to the line 3y + 2x + 7 = 0?

A. 3y + 2x - 7 = 0

B. 9y + 6x + 17 = 0

C. 24y + 16x + 19 = 0

D. 3y - 2x + 7 = 0

E. 15y + 10x - 13 = 0

Detailed Solution

Two lines are said to be parallel if the slope of the two lines are equal.
The equation : \(3y + 2x + 7 = 0\)
\(3y = -2x - 7\)
\(y = \frac{-2}{3} x - \frac{7}{3}\)
\(\frac{\mathrm d y}{\mathrm d x} = - \frac{2}{3}\)
All the options have the same slope except \(3y - 2x + 7 = 0\).
1.

Rationalize the expression \(\frac{1}{\sqrt{2} + \sqrt{5}}\)

A. \(\frac{1}{3}\)(\(\sqrt{5} - \sqrt{2}\)

B. \(\frac{\sqrt{2}}{3}\) + \(\frac{\sqrt{5}}{5}\)

C. \(\sqrt{2} - \sqrt{5}\)

D. 5(\(\sqrt{2} - \sqrt{5}\)

E. \(\frac{1}{3}\)(\(\sqrt{2} - \sqrt{5}\)

Detailed Solution

\(\frac{1}{\sqrt{2} + \sqrt{5}}\)
\(\frac{1}{\sqrt{2} + \sqrt{5}} \times \frac{(\sqrt{2} - \sqrt{5})}{(\sqrt{2} - \sqrt{5})}\)
= \(\frac{\sqrt{2} - \sqrt{5}}{2 - 5}\)
= \(\frac{\sqrt{2} - \sqrt{5}}{-3}\)
= \(\frac{1}{3} (\sqrt{5} - \sqrt{2})\)
2.

Simplify 3 - 2 \(\div\) \(\frac{4}{5}\) + \(\frac{1}{2}\)

A. 1\(\frac{3}{4}\)

B. -1

C. 1\(\frac{3}{10}\)

D. 1

E. 1\(\frac{9}{10}\)

Detailed Solution

3 - 2 \(\div\) (\(\frac{4}{5}\)) + \(\frac{1}{2}\)

3 - (2 x \(\frac{5}{4}\)) + \(\frac{1}{2}\) = 3 - \(\frac{10}{4}\) + \(\frac{1}{2}\)

= 3 - \(\frac{5}{2}\) + \(\frac{1}{2}\)

= \(\frac{6 - 5 + 1}{2}\)

= \(\frac{2}{2}\)

= 1
3.

If N560.70 is shared in the ratio 7 : 2 : 1, what is the smallest share?

A. N392.49

B. N56.70

C. N113.40

D. N112.14

E. N56.07

Detailed Solution

7 + 2 + 1 = 10

\(\frac{1}{10}\) x 560.70

= N56.07
4.

Seven years ago, the age of a father was three times that of his son, but in six years time the age of the son will be half that of his father, representing the present ages of the father and son by x and y, respectively, the two equations relating x and y are

A. 3y - x = 0; 2y - x = 0

B. 3y - x = 14; x - 2y = 6

C. 3y - x =7; x - 2y = 6

D. 3y - x = 14; y - 2x = 6

E. x + 3y = 7; x = 2y = 12

Detailed Solution

7 years ago, Father(x - 7) years old, Son (y - 7) years

x - 7 = 3(y - 7)
x - 7 = 3y - 21
3y - x = -7 + 21 = 14
3y - x = 14 ... (1)
In six years time,
x + 6 = 2(y + 6)
x + 6 = 2y + 12
2y + 12 = x + 6
12 - 6 = x - 2y
6 = x - 2y ... (2)
5.

The factors of 6x - 5 - x2 are

A. -(x + 3)(x + 2)

B. (x + 5)(x + 1)

C. (x - 5)(1 - x)

D. (x + 1)(x + 5)

Detailed Solution

6x - 5 - x2 = (-1)(-x2 - 5 + 6x)

= x2 - 6x + 5

= (x - 5)(x - 1)

-(x - 1) = 1 - x

= (x - 5)(1 - x)
6.

The solution of the quadratic equation bx2 + cx + a = 0 is given by

A. x = b \(\pm\) \(\frac{\sqrt{b^2 - 4ac}}{2a}\)

B. x = c \(\pm\) \(\frac{\sqrt{b^2 - 4ab}}{2b}\)

C. x = -c \(\pm\) \(\frac{\sqrt{c^2 - 4ab}}{2b}\)

D. x = -b \(\pm\) \(\frac{\sqrt{b^2 - 4ac}}{2b}\)

Detailed Solution

bx2 + cx + a = 0

a = b; b = c; c = a

x = -b \(\pm\) \(\frac{\sqrt{b^2 - 4ac}}{2a}\)

x = -c \(\pm\) \(\frac{\sqrt{c^2 - 4ab}}{2b}\)
7.

The graphical method of solving the equation x3 + 3x2 + 4x - 28 = 0 is by drawing the graphs of the curves

A. y = x3 and y = 3x2 + x - 28

B. y = x3 + 3x2 + 4x + 4 and the line y = \(\frac{28}{x}\)

C. y = x3 + 3x2 + 4x and y

D. y = x2 + 3x + 4 and y = \(\frac{28}{x}\)

E. y = x2 + 3x + 4 and line y = 28x

Detailed Solution

The graphical method of solving the equation x3 + 3x2 + 4x - 28 = 0 is by drawing the graphs of the curves

y = x2 + 3x + 4 and y = \(\frac{28}{x}\)`.
8.

Write the equation 2 log2x - x log2(1 + y) = 3 in a form not involving logarithms

A. 2x(1 + y) = 3

B. 2x - x(1 + y) = 8

C. x2 = 8(1 + y)x

D. x2 - x(1 + y) = 8

E. x2 - (1 + y)2 = 8

Detailed Solution

2log2 x - x log2 (1 + y) = 3

log2 \(\frac{x^2}{(1 + y)^x}\) = 3

= \(\frac{x^2}{(1 + y)^x}\)

= 23

= 8

= x2 = 8(1 + y)x
9.

Find \(\alpha\) and \(\beta\) such that x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x (\(\frac{y^{\frac{9}{7}}}{x^{\frac{45}{8}}}\))\(\frac{1}{9}\) = \(\frac{y^{\alpha}}{y^{\beta}}\)

A. \(\alpha\) = 1, \(\beta\) = \(\frac{5}{7}\)

B. \(\alpha\)= 1, \(\beta\) = -\(\frac{5}{7}\)

C. \(\alpha\)= \(\frac{3}{5}\), \(\beta\) = -6

D. \(\alpha\)= 1, \(\beta\) = -\(\frac{3}{5}\)

Detailed Solution

x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x (\(\frac{y^{\frac{9}{7}}}{x^{\frac{45}{8}}}\))\(\frac{1}{9}\) = \(\frac{y^{\alpha}}{y^{\beta}}\)

x\(\frac{3}{8}\) x y\(\frac{-6}{7}\) x y\(\frac{1}{7}\) = x\(\alpha\)

= x\(\frac{3}{8}\) + \(\frac{5}{8}\) + y\(\frac{6}{7}\) + \(\frac{1}{7}\)

= x\(\alpha\)y\(\beta\)

x1y\(\frac{-5}{7}\) = x\(\alpha\)y\(\beta\)

\(\alpha\) = 1, \(\beta\) = \(\frac{5}{7}\)
10.

Which of the following lines is not parallel to the line 3y + 2x + 7 = 0?

A. 3y + 2x - 7 = 0

B. 9y + 6x + 17 = 0

C. 24y + 16x + 19 = 0

D. 3y - 2x + 7 = 0

E. 15y + 10x - 13 = 0

Detailed Solution

Two lines are said to be parallel if the slope of the two lines are equal.
The equation : \(3y + 2x + 7 = 0\)
\(3y = -2x - 7\)
\(y = \frac{-2}{3} x - \frac{7}{3}\)
\(\frac{\mathrm d y}{\mathrm d x} = - \frac{2}{3}\)
All the options have the same slope except \(3y - 2x + 7 = 0\).