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solving trig qn (1 Viewer)

sarah.maddison

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the q is solve tan x = 2 sin x, where -pi < x <= pi. I can find the answers +- pi/3 easily, but the answer key says the answer is the above and also 0 and pi. where did those two come from?
 

jumb

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Exphate said:
Graph the two, identify the points etc etc.

Zero and pi are elementary: The both equal 0 for both equations.
tan(pi) = infinite

The answers are wrong, I plotted what you said to double check and its only at +/- acos(1/2)

edit: oh wait, that's pi/2. Yeah, exphate is right.
 

Psychokiller

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sarah.maddison said:
the q is solve tan x = 2 sin x, where -pi < x <= pi. I can find the answers +- pi/3 easily, but the answer key says the answer is the above and also 0 and pi. where did those two come from?
solve sin x = sin 2x
 

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