Year : 
1993
Title : 
Mathematics (Core)
Exam : 
JAMB Exam

Paper 1 | Objectives

1 - 10 of 51 Questions

# Question Ans
1.

Integrate \(\frac{1 - x}{x^3}\) with respect to x

A. \(\frac{x - x^2}{x^4}\) + k

B. \(\frac{4}{x^4} - \frac{3 + k}{x^3}\)

C. \(\frac{1}{x} - \frac{1}{2x^2}\) + k

D. \(\frac{1}{3x^2} - \frac{1}{2x}\) + k

Detailed Solution

\(\int \frac{1 - x}{x^3}\)

= \(\int^{1}_{x^3} - \int^{x}_{x^3}\)

= x-3 dx - x-2dx

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

Change 7110 to base 8

A. 1078

B. 1068

C. 718

D. 178

Detailed Solution

\(\begin{array}{c|c} 8 & 71 \\ 8 & 8 \text{rem} 7\\ 8 & 1 \text{rem} 0\end{array}\)

= 1078
3.

Evaluate \(\frac{3524}{0.05}\) correct to 3 significant figures

A. 705

B. 70,000

C. 70, 480

D. 70, 500

Detailed Solution

\(\frac{3524}{0.05}\) = 70480

\(\approx\) 70500(3 s.g)
4.

If 9(x - \(\frac{1}{2}\)) 3x2

A. \(\frac{1}{2}\)

B. 1

C. 2

D. 3

Detailed Solution

9(x - \(\frac{1}{2}\)) 3x2 = 32(x - \(\frac{1}{2}\)) = 3x2
∴ 2(x - \(\frac{1}{2}\)) = x2

2x - 1 = x2

hence x2 - 2x + 1 = 0

(x - 1)(x - 1) = 0

x = 1
5.

Solve for y in the equation 10^1 x 5(2y - 2) x 4(y - 1) = 1

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

B. \(\frac{5}{4}\)

C. \(\frac{2}{3}\)

D. 5

Detailed Solution

10y x 5(2y - 2) x 4(y - 1) = 1

but 10y - (5 x 2)y = 5y x 2y

= (Law of indices)

5y x 2y x 5(2y - 2) x 4(y - 1) = 1

but 4(y - 1) = 22(y - 1)

= 2y - 2 (Law of indices)

5y x 5(2y -2) x 2(- 2) = 1

5(3y -2) x 2y x 2(2y -2) = 1

= 5(3y -2) x 2(3y -2) = 1

But ao = 1

10(3y -2) = 10o

3y - 2 = 0

∴ y = \(\frac{2}{3}\)
6.

Simplify \(\frac{1}{√3 - 2}\) - \(\frac{1}{√3 + 2}\)

A. 3

B. \(\frac{2}{3}\)

C. 7

D. -4

Detailed Solution

\(\frac{1}{√3 - 2}\) - \(\frac{1}{√3 + 2}\)

L.C.M = (3- 2) (3 + 2)

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


\(\frac{√3 + 2 - √3 + 2}{3 - 2√3 + 2√3 - 4}\) = \(\frac{4}{3 - 2}\)

= \(\frac{4}{-1}\)

= -4
7.

If 2log3 y + log3 x2 = 4, then y is

A. 4 - log3

B. \(\frac{4}{log_3 x}\)

C. \(\frac{4}{x}\)

D. \(\pm\) \(\frac{9}{x}\)

Detailed Solution

2log3y + log3x2 = 4

log3y2 + log3x2 = 4

∴ log3 (x2y2) = log381(correct all to base 4)

x2y2 = 81

∴ xy = \(\pm\)9

∴ y = \(\pm\)\(\frac{9}{x}\)
8.

Solve without using tables log5(62.5) - log5(\(\frac{1}{2}\))

A. 3

B. 4

C. 5

D. 8

Detailed Solution

log5(62.5) - log5(\(\frac{1}{2}\))

= log5\(\frac{(62.5)}{\frac{1}{2}}\) - log5(2 x 62.5)

= log5(125)

= log553 - 3log55

= 3
9.

If N225.00 yields N27.00 in x years simple interest at the rate of 4% per annum, find x

A. 3

B. 4

C. 12

D. 17

Detailed Solution

Principal = N255.00, Interest = 27.00

year = x Rate: 4%

∴ 1 = \(\frac{PRT}{100}\)

27 = \(\frac{225 \times 4 \times T}{100}\)

2700 = 900T

T = 3 years
10.

If \(\sqrt{x^2 + 9}\) = x + 1, solve for x

A. 5

B. 4

C. 3

D. 2

E. 1

Detailed Solution

\(\sqrt{x^2 + 9}\) = x + 1

x2 + 9 = (x + 1)2 + 1

0 = x2 + 2x + 1 - x2 - 9

= 2x - 8 = 0

2(x - 4) = 0

x = 4
1.

Integrate \(\frac{1 - x}{x^3}\) with respect to x

A. \(\frac{x - x^2}{x^4}\) + k

B. \(\frac{4}{x^4} - \frac{3 + k}{x^3}\)

C. \(\frac{1}{x} - \frac{1}{2x^2}\) + k

D. \(\frac{1}{3x^2} - \frac{1}{2x}\) + k

Detailed Solution

\(\int \frac{1 - x}{x^3}\)

= \(\int^{1}_{x^3} - \int^{x}_{x^3}\)

= x-3 dx - x-2dx

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

Change 7110 to base 8

A. 1078

B. 1068

C. 718

D. 178

Detailed Solution

\(\begin{array}{c|c} 8 & 71 \\ 8 & 8 \text{rem} 7\\ 8 & 1 \text{rem} 0\end{array}\)

= 1078
3.

Evaluate \(\frac{3524}{0.05}\) correct to 3 significant figures

A. 705

B. 70,000

C. 70, 480

D. 70, 500

Detailed Solution

\(\frac{3524}{0.05}\) = 70480

\(\approx\) 70500(3 s.g)
4.

If 9(x - \(\frac{1}{2}\)) 3x2

A. \(\frac{1}{2}\)

B. 1

C. 2

D. 3

Detailed Solution

9(x - \(\frac{1}{2}\)) 3x2 = 32(x - \(\frac{1}{2}\)) = 3x2
∴ 2(x - \(\frac{1}{2}\)) = x2

2x - 1 = x2

hence x2 - 2x + 1 = 0

(x - 1)(x - 1) = 0

x = 1
5.

Solve for y in the equation 10^1 x 5(2y - 2) x 4(y - 1) = 1

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

B. \(\frac{5}{4}\)

C. \(\frac{2}{3}\)

D. 5

Detailed Solution

10y x 5(2y - 2) x 4(y - 1) = 1

but 10y - (5 x 2)y = 5y x 2y

= (Law of indices)

5y x 2y x 5(2y - 2) x 4(y - 1) = 1

but 4(y - 1) = 22(y - 1)

= 2y - 2 (Law of indices)

5y x 5(2y -2) x 2(- 2) = 1

5(3y -2) x 2y x 2(2y -2) = 1

= 5(3y -2) x 2(3y -2) = 1

But ao = 1

10(3y -2) = 10o

3y - 2 = 0

∴ y = \(\frac{2}{3}\)
6.

Simplify \(\frac{1}{√3 - 2}\) - \(\frac{1}{√3 + 2}\)

A. 3

B. \(\frac{2}{3}\)

C. 7

D. -4

Detailed Solution

\(\frac{1}{√3 - 2}\) - \(\frac{1}{√3 + 2}\)

L.C.M = (3- 2) (3 + 2)

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


\(\frac{√3 + 2 - √3 + 2}{3 - 2√3 + 2√3 - 4}\) = \(\frac{4}{3 - 2}\)

= \(\frac{4}{-1}\)

= -4
7.

If 2log3 y + log3 x2 = 4, then y is

A. 4 - log3

B. \(\frac{4}{log_3 x}\)

C. \(\frac{4}{x}\)

D. \(\pm\) \(\frac{9}{x}\)

Detailed Solution

2log3y + log3x2 = 4

log3y2 + log3x2 = 4

∴ log3 (x2y2) = log381(correct all to base 4)

x2y2 = 81

∴ xy = \(\pm\)9

∴ y = \(\pm\)\(\frac{9}{x}\)
8.

Solve without using tables log5(62.5) - log5(\(\frac{1}{2}\))

A. 3

B. 4

C. 5

D. 8

Detailed Solution

log5(62.5) - log5(\(\frac{1}{2}\))

= log5\(\frac{(62.5)}{\frac{1}{2}}\) - log5(2 x 62.5)

= log5(125)

= log553 - 3log55

= 3
9.

If N225.00 yields N27.00 in x years simple interest at the rate of 4% per annum, find x

A. 3

B. 4

C. 12

D. 17

Detailed Solution

Principal = N255.00, Interest = 27.00

year = x Rate: 4%

∴ 1 = \(\frac{PRT}{100}\)

27 = \(\frac{225 \times 4 \times T}{100}\)

2700 = 900T

T = 3 years
10.

If \(\sqrt{x^2 + 9}\) = x + 1, solve for x

A. 5

B. 4

C. 3

D. 2

E. 1

Detailed Solution

\(\sqrt{x^2 + 9}\) = x + 1

x2 + 9 = (x + 1)2 + 1

0 = x2 + 2x + 1 - x2 - 9

= 2x - 8 = 0

2(x - 4) = 0

x = 4