Math gr.12 Trig.
Hi, could someone explain to me how to use a counterexample in trig to prove whether something is either an identity or equation?
For ex. how would you do that with this question?
sec^2xtan^2x= cos x
asked by
May

A counterexample is simply any instance that disproves the statement.
For example, try using x = pi/4. Note that this is NOT the only correct answer.posted by Marth

Would I substitute the same number to both sides?
posted by May
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