Recent content by Mstenbach

Aha! I see it now. The range of cos is between 1 and -1, so it cannot exceed 1... I think I see that now. Just one question, how did you find "cosc"? Thank you very much.

Hmm, ok, thank you. So I get now |sinb - sina| __________ <= 1 | b - a| Which is similar to the theorem f(b)-f(a) / b-a ? If it is, this basically says that the equation I came up with (which is the derivative) is equal to 1? Can I work on this further by taking the...

Well, my guess is it does but I still fail to see any connection. | \sin \displaystyle x- \sin \displaystyle y| = 2 \left| \cos \left( \frac{\displaystyle x+ \displaystyle y}{2} \right) \sin \left( \frac{\displaystyle x- \displaystyle y}{2} \right) \right| Am I getting anywhere with this?

Reading the hotlink I still fail to see the connection with MVT to the problem. Could the "real values x and y" have anything to do with the (a, b) interval?

Homework Statement Prove for all real x and y that |sinx - siny| <= |x-y| Homework Equations It's a question from the Mean Value Theorem/Rolle's Theorem section. The Attempt at a Solution Honestly, I've tried. It looks somewhat similar to the triangle inequality (I think?), but...