trig

[UrbanXrisis]

y=2 ln(secx)
x=pi/4

what does y equal?

cos45=sqrt(2)/2
sec45=2/sqrt(2)

y=2* ln(2/sqrt(2))

what is the natural log of 2/sqrt(2)?

[maverick280857]

Do you know that

\ln(a^n) = n\ln(a) if a>0?

Using this

y = 2\ln(\frac{2}{\sqrt{2}}) = 2\ln(\sqrt{2}) = \frac{2}{2}\ln(2)