proving x.(3+cosx)>2sinx

emreyunus

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x.(3+cosx)>2sinx , x>0 I should solve this problem with mean value teorem and I am not sure how to because of x>0 but not x>=0.
 

Subhotosh Khan

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emreyunus

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Jomo

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okay, after applying this I could show that sinx<x for x>0 and its done, thanks
Maybe so, but you are required to use the mean value theorem.
 

emreyunus

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okay, after applying this I could show that sinx<x for x>0 and its done, thanks
I have a similiar question but this time that rule seems like can not help. Then how we can prove x.(2+cosx)>3sinx
 

emreyunus

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JeffM

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I have a similiar question but this time that rule seems like can not help. Then how we can prove x.(2+cosx)>3sinx
You cannot prove that because it is not true.

\(\displaystyle 0\{2 + cos(0)\} = 0(2 + 1) = 0 * 3 = 0 \not > 0 = 3sin(0).\)
 

emreyunus

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You cannot prove that because it is not true.

\(\displaystyle 0\{2 + cos(0)\} = 0(2 + 1) = 0 * 3 = 0 \not > 0 = 3sin(0).\)
yes, sorry I didnt mention x>0 again
 
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