GEOMETRY AND TRIGONOMETRY - Jamb Mathematics Past Questions and Answers

Question 121:

• JAMB 1978

Evaluate without using tables sin(-1290^o)

A. \(\frac{3}{2}\)
B. -\(\frac{3}{2}\)
C. \(\frac{2}{2}\)
D. 1
E. \(\frac{1}{2}\)

Question 122:

• JAMB 1978

The angle of elevation of the top of a vertical tower from a point A on the ground is 60^o. From a point B, 2 units of distance further away from the foot of the tower, the angle of elevation of the tower is 45^o. Find the distance of A from the foot of the tower

A. 3 + \(\sqrt{3}\)
B. 5 + \(\sqrt{3}\)
C. 3 - \(\sqrt{3}\)
D. 1
E. \(\sqrt{3}\) - 1

Question 123:

• JAMB 1978

The vectors a and b are given in terms of two perpendicular units vectors i and j on a plane by a = 2i - 3j, b = -i + 2j. Find the magnitude of the vector a + 3b

A. 2
B. 4
C. \(\sqrt{10}\)
D. 35
E. 2.2

Question 124:

• JAMB 1978

In the figure, DE//BC: DB//FE: DE = 2cm, FC = 3cm, AE = 4cm. Determine the length of EC.

A. 4cm
B. 6cm
C. 3cm
D. 2cm
E. 1cm

Question 125:

• JAMB 1978

In the figure, AB is parallel to CD then x + y + z is

A. 185^o
B. 200^o
C. 270^o
D. 360^o
E. 195^o