Trig. equations : Edexcel Core Maths C3 January 2012 Q5 : ExamSolutions

[Harvstermysterinator]

Has there ever been an easier 10 mark question on C3?

[TukedoPenguin]

sorry about nit picking but should be 160.529 as one answer for 3θ not 160.528, apart form that i love your videos they are a life saver... like right now about 10hours before my C3 exam.

[hackj]

I suppose you could do that, the way I did it I think feels more "natural" instead of forcing cot^2 x to become cosec^2 x, I moved two over so it was
2 ( cot^2 3(-) ) + 2 =7cosec 3(-) - 3
then I moved the +2 into the brackets so it could give me
2 (cot^2 3(-) + 1 ) =7cosec 3(-) - 3

Then I used 1+cot^2 (-) = cosec^2 (-)

Feels quicker for me

[AlexJWesto]

this question cost me a grade on the exam

[megamagicstars]

I changed the trig functions to in terms of cos and sin, and i had to use the quadratic formula... which lead me to the wrong answer..
but i still don't understand how my method doesn't work?