in part(adsbygoogle = window.adsbygoogle || []).push({}); b) iof a question, i was asked to prove that (1-cos2x)/sin2x is equivilent to tanx and so i did.

then in partb) iii was asked to varify that 180 is a solution of x for:

sin2x = 2 - 2cos2x

i took the 2 out; sin2x = 2(1 - cos2x) and saw similarities to parti,

so i divided by 2sin2x to get

(1-cos2x)/sin2x = 1/2

which using partii deduced that tanx = 1/2

but 180 isnt the solution of this. (26.6 is)

where did I go wrong, was it because I divided through by a the 2sin2x when i shouldn't have?

in my https://www.physicsforums.com/showthread.php?t=165036" it was apparently ok to divide by a trig funtion, if this is the problem here why does it apply to this and not my other question

NB partaof the question seems irrelevant.

partb) iiihowever asks me to find the other 2 solutions, of which 26.6 is one of the answers

so how do i get to 180 and the other solution for partb) iii

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# Homework Help: Another trigonometry problem

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