Question 1082372
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This statement is WRONG.


As a counter-example consider the angle of 45 degs.


Then sin(x) = {{{sqrt(2)/2}}}, cot(x) = 1, cos(x) = {{{sqrt(2)/2}}}.


Do you have the equality in this case ?



I have one more question: for what reason do you post wrong/false statements to this forum ?