SOLUTION: Why we should solve like this???
If {{{CosX = -1/2}}}
{{{CosX = Cos(2(pi)/3)}}}
{{{X = 2n(pi) +- 2(pi)/3}}}
Why we can't do like this?
{{{CosX = -1/2}}}
{{{CosX =
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Question 895868: Why we should solve like this???
If
Why we can't do like this?
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Why we should solve like this???
If
Why we can't do like this?
********** cos(-pi/3) <> -1/2
----------
cos(-pi/3) = cos(pi/3) = +1/2, not -1/2
**********************************************
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