show that Show that cosx>1-(x²/2) "x>0 o "x<0
hint:for x>0, you can use Mean value theorem for f(x)=cosx+(x²/2) on [0,x]
Thank you ..
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I think the best method is to use Taylor's Theorem - it gives the expansion for in powers of x as . The error term is where c is some number between x and 0. Since this error term is positive, for all .
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