Mean value theorem(mvt) to prove the inequality

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Khayyam89
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Homework Statement


Essentially, the question asks to use the mean value theorem(mvt) to prove the inequality: [tex]\left|[/tex]sin a -sin b [tex]\right|[/tex] [tex]\leq[/tex] [tex]\left|[/tex] a - b[tex]\right|[/tex] for all a and b


The Attempt at a Solution



I do not have a graphing calculator nor can I use one for this problem, so I need to prove that the inequality basically by proof. What I did was to look at the mvt hypotheses: if the function is continuous and differetiable on closed and open on interval a,b, respectively. However, the problem I am having is that I am getting thrown off by the absolute values and the fact that I've never used mvt on inequalities. I know the absolute value of the sin will look like a sequence of upside-down cups with vertical tangents between them. Hints most appreciated.
 
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The mean value theorem states that in an interval [a,b]:

[tex]f'(c) = \frac{ \sin b - \sin a}{b-a} = \cos(c)[/tex]

Now put absolute value signs there and make use of [tex]|\cos(x)| \leq 1[/tex]