How do you find the exact value of $cos^-1(sinpi)$ ?

Question

3544 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-09-07T14:18:12

$-pi/2$

Use $sin a = cos (pi/2-a).and f^(-1)f(x)=x$ .

Here, the given expression is

$cos^(-1)(sin pi)$

$=cos^(-1)(cos(pi/2-pi))$

$=pi/2-pi$

$=-pi/2$

How do you find the exact value of cos^-1(sinpi)cos^-1(sinpi)?