Trig. Equations : Factorising Types f(x)=0 : (Example 1) : ExamSolutions

[Nenjaw]

Something's confusing me a bit.

Where you had (1-2cosx)=o

When you rearranged it and took the +(1) to the other side, you had:

2cosx=+(1)

Shouldn't it have been:

-2cosx=-1

and then when you divided both sides by -2, you'd have been left with:

cosx= +(1/2) -> (I know it doesn't make a difference to the final answer, but you had me confused to pieces for a good few minutes lol).

Other than that, nice video, meng.

[ExamSolutions]

@Nenjaw I added 2cos(x) to both sides so 1 = 2cos(x) but I reversed it to say 2cos(x) = 1.

[Nenjaw]

@ExamSolutions Ohhh, well that explains it.

Thanks for the fast response.

[TheLittleTrickster]

The solutions are very helpful and well explained, problem is my mind wanders somewhere else when listening to your voice. Not to sound harsh, but your voice sounds very boring. Other than that, thanks for making these videos. They've been extremely helpful.

[Goodfellow7]

@TheLittleTrickste On the boring comment... I don't find his voice boring at all, and find his methodical approach very freshing and easy to taken in, compared to the khanacademy whose jumbled/caffiene fuelled style gives me a headache!

[Y5FK]

Isn't 300 degress meant to be minus, because its in the tan quadrent ?

[ShiverZ92]

@Y5FK It's in the Cos quadrent