(a) Copy and complete the table of the relation \(y = 2\sin x - \cos 2x\).
x
0^\circ
30^\circ
60^\circ
90^\circ
120^\circ
150^\circ
180^\circ
y
0.5
-1.0
Using a scale of 2 cm to 30^\circ 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 \(0^\circ \leq x \leq 180^\circ\).
(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 \(2\sin x - \cos 2x = 1.25\).
Verified Correct Answer: .
Step-by-Step Mathematical Solution
(a) \(y = 2\sin x - \cos 2x\)
x
0^\circ
30^\circ
60^\circ
90^\circ
120^\circ
150^\circ
180^\circ
y
-1.0
0.5
2.2
3.0
2.2
0.5
-1.0
(b)
Source: Myschool Past Questions Archive (Record #53053)