Hi Jessie W,
( Jessie Lau, in case you are reading this, this post is not for you! hehe! I have another student by the name of Jessie this year. )
Here are the 3 questions on Trigo Double Angle!
Please attempt and complete these questions together with the homework I gave during class.
You may key your answers in the comments column below so that I can check your answers before class and save some time. 🙂
(1) Given that cos x = -0.6 and that ∏ < x < 3∏/2 , find without using calculator, the value of
(a) sin 2x
(b) tan 4x
(2) Find all the values of x between 00 and 3600 inclusive which satisfy the equation
(a) 4cos 2x – 3sin x + 1 =0
(b) 2cot 2x =5
(3) The function f is defined by f(x) = 4cos 2x-2
(a) State the amplitude of f
(b) State the period of f
The equation of a curve is y = 4cos 2x -2 for 00 < x < 1800
(c) Find the coordinates of the minimum point of the curve
(d) Find the coordinates of the points where the curve meets the x-axis
(e) Sketch the graph of y = |4cos 2x -2| for 00 < x < 1800
* Q3 is N2008/P2/Q7