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C2, Trig identities

I really struggle with the C2 chapter of Trig identities and simple equations....
We haven't covered it in college yet but I watched the hegarty maths videos on the chapter..

I get it, but I keep getting the mixed exercises wrong :frown:
I don't understand the method of the questions, and for each one it is so different, this is why I am struggling with it.

Are there any resources anyone knows about I can use?
Or any tips on the methods?

A few of the Qs (0= theta, o = 0)-
Factorise 4xy - y^2 + 4x - y
Hence solve the equation 4sin0cos0 -cos^20 + 4sin0 -cos0 = o, in the interval o - 360

Find, in radian to 2 dec place, the value of x in the interval o - 2pi, for which 3sin^2x + sinx -2 = o
Original post by Ruineth
I really struggle with the C2 chapter of Trig identities and simple equations....
We haven't covered it in college yet but I watched the hegarty maths videos on the chapter..

I get it, but I keep getting the mixed exercises wrong :frown:
I don't understand the method of the questions, and for each one it is so different, this is why I am struggling with it.

Are there any resources anyone knows about I can use?
Or any tips on the methods?

A few of the Qs (0= theta, o = 0)-
Factorise 4xy - y^2 + 4x - y
Hence solve the equation 4sin0cos0 -cos^20 + 4sin0 -cos0 = o, in the interval o - 360

Find, in radian to 2 dec place, the value of x in the interval o - 2pi, for which 3sin^2x + sinx -2 = o


Trig is all about practice. The tough thing about it is that the method changes for each question, as you say. You're not expected to memorise each one - but you're supposed to figure out what to do. This just takes time/practice and hopefully you'll get it eventually.

For the first question you've posted see how the first part of the question links to the second part of the question.

For the second part, it may help you to substitute y = sinx and then solve that as you would a quadratic.

If you haven't covered it in class don't stress too much, you may understand it then. I've heard that examsolutions is a good website to use for Maths.

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