cos30=sin多少度

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• What is the difference between sin30 and sin 30 degreeHi!Currently,I am studying trigonometry,and I bought a new Texas Instrument Calculator that was made in China.But When I input sin (30),it gave me an answer of -0.9880316241.That is freaking incorrect.But trickily,when I input sin (30ْ),it gave 0.5 which is a correct one.Additionally,I need to work on huge math packet everyday; so I want to get it done as fast as possible.And I at least need to pre
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