二年級(jí)數(shù)學(xué)上冊(cè)課件（人教版）角的初步認(rèn)識(shí)第3課時(shí)銳角的初步認(rèn)識(shí)EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET1.結(jié)合生活情境認(rèn)識(shí)角;經(jīng)歷從實(shí)際物體中抽象出簡(jiǎn)單平面圖形的過程,掌握初步的畫圖技能2.在從物體中抽象出幾何圖形的過程中,發(fā)展空間觀念;在觀察、操作活動(dòng)中,能提出一些簡(jiǎn)單的猜想,并會(huì)獨(dú)立思考問題,表達(dá)自己的想法;體驗(yàn)與他人合作交流解決問題的過程。EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET角角成長(zhǎng)記EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NETEvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET

角的兩邊張口越大，角越大。EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NETEvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NETEvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET

角的兩邊張口越小，角越小。EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET綠色圃中小學(xué)教育網(wǎng)比直角小EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET？誰聰明誰來猜EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET？誰聰明誰來猜EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET銳角誰聰明誰來猜EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET指出里面的銳角前兩個(gè)是銳角EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET總結(jié)：小小角，真簡(jiǎn)單，一個(gè)頂點(diǎn)兩條邊。畫角時(shí)，要牢記，先畫頂點(diǎn)再畫邊。EvaluationWarning:ThedocumentwascreatedwithSpire.Presentationfor.NET判斷:×√√⑴邊越長(zhǎng),角就越大。()⑵角的大小與邊的長(zhǎng)短無關(guān)。()⑶一個(gè)角只有兩條邊,一個(gè)頂點(diǎn)。()