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# √3tanx = 2sinx watch

1. Need to solve, range is -180<= 0 <= 180.
I got 30 and -30, but there are 3 more values for which x is -180, 0 and 180 given in the answer. Can anyone explain why?
Thanks
2. (Original post by Bilbao)
Need to solve, range is -180<= 0 <= 180.
I got 30 and -30, but there are 3 more values for which x is -180, 0 and 180 given in the answer. Can anyone explain why?
Thanks
Because you've seen and cancelled them out instead of factoring them.

An example would be x^2 = x. Dividing both sides by x yields x = 1. Factoring gives x^2 - x = x(x-1) = 0, giving x=0 also.

Never cancel trig functions out through division, only when you have something like sinx = cosx, then you can make that tanx = 1.

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