【題目】在飛機(jī)飛行時(shí),飛行方向是用飛行路線與實(shí)際的南或北方向線之間的夾角大小來(lái)表示的,如圖,用AN(南北線)與飛行線之間順時(shí)針?lè)较驃A角作為飛行方向角,從A到B的飛行方向角為35°,從A到C的飛行方向角為60°,從A到D的飛行方向角為145°,試求AB與AC之間夾角為多少度?AD與AC之間夾角為多少度?并畫出從A飛出且方向角為105°的飛行線.

【答案】答案見(jiàn)解析.

【解析】本題考查的是方位角

閱讀題目條件，明確飛機(jī)飛行角的概念，找到南北線與飛行線之間順時(shí)針?lè)较驃A角，計(jì)算其角度解答．

由題意可知∠NAB=35°，∠NAC=60°，∠NAD=145°．

故AB與AC之間夾角為∠NAC-∠NAB=60°-35°=25°，

AD與AC之間夾角為∠NAD-∠NAC=145°-60°=85°．

思路拓展：此題是一道材料分析題，解答時(shí)要認(rèn)真閱讀，明確題目條件，特別是題目中的新概念，依據(jù)新概念解答．

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