Question Detail
Question
Which option is incorrect? A. cosh²x-sinh²x=1 B. cosh²x+sinh²x=cosh2x C. tanhx=sinhx/coshx D. 1-cosh²x=sinh²x
Correct Answer
Option D is the correct answer.
Detailed Explanation
The correct hyperbolic identity is cosh²x-sinh²x=1, which rearranges to 1-cosh²x=-sinh²x, not +sinh²x. So statement D is the incorrect one.
Hint
Compare each statement to the fundamental identity cosh²x-sinh²x=1.