Problem 115 of 7
Identify invalid cofunction statement cos(10)=sin(90).
Hints
Using a hint is okay. It just tells the trainer to give you a little more review.
Hidden until you reveal it.
catch non-complementary angles and tangent confusion.
Hidden until you reveal it.
Check complementarity and function pair.
Enter your answer
No answer yet
Correct
Your answer is equivalent to the expected form.
Solution
Walkthrough
Walkthrough shown
Full solution stays hidden until you ask for it.
1. Check whether angles sum to 90 degrees.
2. Check whether functions are sine and cosine.
3. State valid or invalid with reason.
Use the worked steps, then substitute the final answer back into the original relationship to confirm it satisfies the prompt.
Validating noncomplementary sine/cosine or tangent confusion.