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Lara1001
prove that limit approaches x to 0 sine delta x/delta x=1
I assume you mean that you want to prove the following: \[\lim_{\Delta x \rightarrow 0} \frac{ \sin \Delta x }{ \Delta x } = 1\] This can be done using L'Hospital's Rule or the Squeeze Theorem. http://tutorial.math.lamar.edu/Classes/CalcI/ProofTrigDeriv.aspx shows a proof using the Squeeze Theorem.