Posted by **calculus** on Sunday, September 18, 2011 at 3:58pm.

cos^-1(cos15pi/6)

- calculus -
**Steve**, Wednesday, September 21, 2011 at 4:17pm
Not much calculus here, but here goes:

by definition

cos(cos^-1(x)) = x

cos^-1(cos(x)) = x

for x in suitable ranges. Now, for cos^-1(x) the function takes on principal values between 0 and π.

So, cos^-1(cos(15π/6)) = cos^-1(cos 5π/2) = cos^-1(0) = π/2.

## Answer this Question

## Related Questions

- calculus - Differentiate. y= (cos x)^x u= cos x du= -sin x dx ln y = ln(cos x)^x...
- Math - Calculus - The identity below is significant because it relates 3 ...
- Calculus - which of the following integrals results from making the substitution...
- Calculus - what is the limit n to infinite of cos1*cos(1/2)*cos(1/4)*cos(1/8)*...
- Calculus - Evaluate (Integral) sin 4x cos^2 4x dx. A. Cos^3(4x)/3 + C B. -Cos^3(...
- Calculus - Evaluate the integral sin4x cos^2 4x dx A. cos^3 4x/3 +C B. - cos^3 ...
- Calculus (help Steve plz) - 1) if w = <-8, 15>, find ||w||? 2) which ...
- calculus - pleaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaasw help can you pleaaaaase ...
- Calculus - Find f'(x) if f(x)=sin^3(4x) A. 4cos^3(4x) B. 3sin^2(4x)cos(4x) C. ...
- Calculus - Let OP be any vector with direction angles theta, beta, and gama. ...