If you input the trig identity:
cot(x)+tan(x)=csc(x)sec(x)
Into WolframAlpha, it gives the following proof:
Expand into basic trigonometric parts:
cos(x)sin(x)+sin(x)cos(x)?=1sin(x)cos(x)
Put over a common denominator:
cos2(x)+sin2(x)cos(x)sin(x)?=1sin(x)cos(x)
Use the Pythagorean identity cos2(x)+sin2(x)=1:
1sin(x)cos(x)?=1sin(x)cos(x)
And finally simplify into
1?=1
The left and right side are identical, so the identity has been verified.
However, I take some issue with this. All this is doing is manipulating a statement that we don't know the veracity of into a true statement. And I've learned that any false statement can prove any true statement, so if this identity was wrong you could also reduce it to a true statement.
Obviously, this proof can be easily adapted into a proof by simply manipulating one side into the other, but:
Is this proof correct on its own? And can the steps WolframAlpha takes be justified, or is it completely wrong?
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