Question 12

(a) Copy and complete the table of the relation \(y = 2\sin x - \cos 2x\).

x 30° 60° 90° 120° 150° 180°
y   0.5         -1.0

Using a scale of 2 cm to 30° on the x- axis and 2 cm to 0.5 unit on the y- axis, draw the graph of \(y = 2\sin x - \cos 2x\), for \(0° \leq x \leq 180°\).

(b) Using the same axes, draw the graph of \(y = 1.25\).

(c) Use your graphs to find the : (i) values of x for which \(2\sin x - \cos 2x = 0\) ; (ii) the roots of the equation \(2\sin x - \cos 2x = 1.25\).

 

Theory

Question details

Exam body
WAEC
Subject
Mathematics
Year
2006
Question no.
#12
Type
Theory

More from this paper

See all Mathematics 2006 questions