SOLUTION: Why we should solve like this? If {{{CosX = -1/2}}} {{{CosX = Cos(2(pi))/3}}} {{{X = 2n(pi) +- 2(pi)/3}}} Why can't we solve like this??? {{{CosX = -1/2}}} {{{Cos

Question 895850: Why we should solve like this?
If

Why can't we solve like this???

Because we can put minus sign inside in Cos...
????
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Why we should solve like this?
If

Why can't we solve like this???

---------------------------
cos(-x) <> -cos(x)
cos(-x) = cos(x)
****************************

Because we can put minus sign inside in Cos...

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