题目

已知0<α<π,sin(π﹣α)+cos(π+α)=m. (1)当m=1时,求α; (2)当时,求tanα的值. 答案:【解答】解:(1)由已知得:sinα﹣cosα=1,所以1﹣2sinαcosα=1,∴sinαcosα=0, 又0<α<π,∴cosα=0,∴. (2)当时,.① ,∴,∴, ∵,∴.② 由①②可得,, ∴tanα=2.As____computer games, all my students love ____ very much. A. for; it        B. to; it         C. /; it        D. for; them
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