How do you differentiate y = cos^-1 (e^-t)y=cos1(et)?

1 Answer
Aug 29, 2015

Differentiate implicitly.

Explanation:

y=cos^-1 (e^(–t))
cos y = e^(–t)

Differentiating wrt t:
–sin y dy/dt = –e^(–t)
–sqrt(1-cos^2 y) dy/dt = –e^(–t)
–sqrt(1-e^(–2t)) dy/dt = –e^(–t)
dy/dt = e^(–t) / sqrt(1-e^(–2t))