Year : 
2007
Title : 
Mathematics (Core)
Exam : 
JAMB Exam

Paper 1 | Objectives

41 - 47 of 47 Questions

# Question Ans
41.

Find the locus of point equidistant from two straight lines y - 5 = 0 and y - 3 = 0

A. y - 2 = 0

B. y - 4 = 0

C. y - 1 = 0

D. y - 3 = 0

Detailed Solution

Locus of point P equidistant from y - 5 = 0 and y - 3 = 0 is y = 4 i.e y - 4 = 0
42.

What is the value of k if the mid-point of the line joining (1 - k, - 4) and (2, k + 1) is (-k , k)?

A. -3

B. -1

C. -4

D. -2

Detailed Solution

(1-k+2) / 2 = - k and -4 + k + 1 = k
3-k = -2k and -3 + k = 2k
K = -3 and k = -3
43.

Find the size of each exterior angle of a regular octagon

A. 51o

B. 45o

C. 40o

D. 36o

Detailed Solution

Each Exterior ∠ = 360/n
= 360/8
= 45o
44.

Find the value of \(\frac{tan 60^o - tan 30^o}{tan 60^o + tan 30^o}\)

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

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

C. 1

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

Detailed Solution

\(\frac{tan 60^o - tan 30^o}{tan 60^o + tan 30^o}= \frac{\sqrt{3}-\frac{1}{\sqrt{3}}}{\sqrt{3}+\frac{1}{\sqrt{3}}}\\
=\left(\frac{\sqrt{3}\sqrt{3}-1}{\sqrt{3}}\right)\div \left(\frac{\sqrt{3}\sqrt{3}+1}{\sqrt{3}}\right)\\
=\frac{(3-1)}{(3+1)}\\
=\frac{2}{4}=\frac{1}{2}\)
45.

The area of a square is 144 sqcm. Find the length of the diagonal.

A. 13 cm

B. 12√2 cm

C. 12 cm

D. 11√3 cm

Detailed Solution

Area of a square = x * x
144 = x2
√144 = x
12 = x
But d2 = 122 x 122
= 144 + 144
= 288
d = √288
= √144 x 2
= 12√2
46.

If y = (1 + x)2, find \(\frac{dy}{dx}\)

A. x - 1

B. 2 + 2x

C. 1 + 2x

D. 2x - 1

Detailed Solution

If y = (1 + x)2, find \(\frac{dy}{dx}\)

y = (1 + x)2

\(\frac{dy}{dx}\) = 2(1 + x)

= 2 + 2x
47.

The sum of the ages of Musa and Lawal is 28 years. After sharing a certain sum of money in the ratio of their ages, Musa gets N600 and Lawal N800. How old is Lawal?

A. 14 years

B. 20 years

C. 12 years

D. 16 years

Detailed Solution

M + L = 28,

M : L = 600 : 800

= 3 : 4

\(\frac{M}{L}\) = \(\frac{3}{4}\) \(\to\) M = \(\frac{3}{4}\)L

\(\frac{3}{4}\)L + L = 28

\(\frac{7L}{4}\) = 28

L = \(\frac{4 \times 28}{7}\)

= 16
41.

Find the locus of point equidistant from two straight lines y - 5 = 0 and y - 3 = 0

A. y - 2 = 0

B. y - 4 = 0

C. y - 1 = 0

D. y - 3 = 0

Detailed Solution

Locus of point P equidistant from y - 5 = 0 and y - 3 = 0 is y = 4 i.e y - 4 = 0
42.

What is the value of k if the mid-point of the line joining (1 - k, - 4) and (2, k + 1) is (-k , k)?

A. -3

B. -1

C. -4

D. -2

Detailed Solution

(1-k+2) / 2 = - k and -4 + k + 1 = k
3-k = -2k and -3 + k = 2k
K = -3 and k = -3
43.

Find the size of each exterior angle of a regular octagon

A. 51o

B. 45o

C. 40o

D. 36o

Detailed Solution

Each Exterior ∠ = 360/n
= 360/8
= 45o
44.

Find the value of \(\frac{tan 60^o - tan 30^o}{tan 60^o + tan 30^o}\)

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

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

C. 1

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

Detailed Solution

\(\frac{tan 60^o - tan 30^o}{tan 60^o + tan 30^o}= \frac{\sqrt{3}-\frac{1}{\sqrt{3}}}{\sqrt{3}+\frac{1}{\sqrt{3}}}\\
=\left(\frac{\sqrt{3}\sqrt{3}-1}{\sqrt{3}}\right)\div \left(\frac{\sqrt{3}\sqrt{3}+1}{\sqrt{3}}\right)\\
=\frac{(3-1)}{(3+1)}\\
=\frac{2}{4}=\frac{1}{2}\)
45.

The area of a square is 144 sqcm. Find the length of the diagonal.

A. 13 cm

B. 12√2 cm

C. 12 cm

D. 11√3 cm

Detailed Solution

Area of a square = x * x
144 = x2
√144 = x
12 = x
But d2 = 122 x 122
= 144 + 144
= 288
d = √288
= √144 x 2
= 12√2
46.

If y = (1 + x)2, find \(\frac{dy}{dx}\)

A. x - 1

B. 2 + 2x

C. 1 + 2x

D. 2x - 1

Detailed Solution

If y = (1 + x)2, find \(\frac{dy}{dx}\)

y = (1 + x)2

\(\frac{dy}{dx}\) = 2(1 + x)

= 2 + 2x
47.

The sum of the ages of Musa and Lawal is 28 years. After sharing a certain sum of money in the ratio of their ages, Musa gets N600 and Lawal N800. How old is Lawal?

A. 14 years

B. 20 years

C. 12 years

D. 16 years

Detailed Solution

M + L = 28,

M : L = 600 : 800

= 3 : 4

\(\frac{M}{L}\) = \(\frac{3}{4}\) \(\to\) M = \(\frac{3}{4}\)L

\(\frac{3}{4}\)L + L = 28

\(\frac{7L}{4}\) = 28

L = \(\frac{4 \times 28}{7}\)

= 16