Question
Question: If \(\cos\alpha\cosh\beta = 1,\) then \(\beta\) is equal to...
If cosαcoshβ=1, then β is equal to
A
logsec(2α)
B
logtanα
C
log(secα+tanα)
D
logsin(2α)
Answer
log(secα+tanα)
Explanation
Solution
cosα.coshβ=1 ⇒ coshβ=secα⇒β=cosh−1(secα) =
log(secα+sec2α−1) = log(secα+tanα)