Set your calculator to DEGREE mode, then use the definition of the derivative to find f(0)\displaystyle {f}'{\left({0}\right)}, when f(x)=sinx\displaystyle {f{{\left({x}\right)}}}={\sin{{x}}}.

By the definition of the derivative,

f(0)=limh0\displaystyle {f}'{\left({0}\right)}=\lim_{{{h}\to{0}}}  


Evaluating this numerically gives f(0)\displaystyle {f}'{\left({0}\right)}\approx   (round your answer to four decimal places)

This suggests
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