0
tanx=2cscx
sinx/cosx=2/sinx
sin2x/cosx=2
sin2x=2cosx
1-cos2x=2cosx
0=cos2x+2cosx-1
cosx=(-2±√(2^2+4))/2
cosx=(-2±√8)/2
cosx=(-2±2√2)/2
cosx=-1±√2
cosx=approximately -2.41 or approximately 0.41.
Since the range of the cosine function is [-1,1], only approx. 0.41 works.
So:
cosx= approx. 0.41
Need calculator now (I went as far as I could without one!)
x=approx 1.148
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