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人教A版高中數(shù)學(xué)必修一集合間的基本關(guān)系教學(xué)設(shè)計(jì)（2）
第一節(jié)通過(guò)研究集合中元素的特點(diǎn)研究了元素與集合之間的關(guān)系及集合的表示方法，而本節(jié)重點(diǎn)通過(guò)研究元素得到兩個(gè)集合之間的關(guān)系，尤其學(xué)生學(xué)完兩個(gè)集合之間的關(guān)系后，一定讓學(xué)生明確元素與集合、集合與集合之間的區(qū)別。課程目標(biāo)1. 了解集合之間包含與相等的含義，能識(shí)別給定集合的子集．2. 理解子集.真子集的概念． 3. 能使用 圖表達(dá)集合間的關(guān)系，體會(huì)直觀圖示對(duì)理解抽象概念的作用。數(shù)學(xué)學(xué)科素養(yǎng)1.數(shù)學(xué)抽象：子集和空集含義的理解；2.邏輯推理：子集、真子集、空集之間的聯(lián)系與區(qū)別；3.數(shù)學(xué)運(yùn)算：由集合間的關(guān)系求參數(shù)的范圍，常見包含一元二次方程及其不等式和不等式組；4.數(shù)據(jù)分析：通過(guò)集合關(guān)系列不等式組， 此過(guò)程中重點(diǎn)關(guān)注端點(diǎn)是否含“=”及 問題；5.數(shù)學(xué)建模：用集合思想對(duì)實(shí)際生活中的對(duì)象進(jìn)行判斷與歸類。
人教A版高中數(shù)學(xué)必修一同角三角函數(shù)的基本關(guān)系教學(xué)設(shè)計(jì)（2）
本節(jié)內(nèi)容是學(xué)生學(xué)習(xí)了任意角和弧度制，任意角的三角函數(shù)后，安排的一節(jié)繼續(xù)深入學(xué)習(xí)內(nèi)容，是求三角函數(shù)值、化簡(jiǎn)三角函數(shù)式、證明三角恒等式的基本工具，是整個(gè)三角函數(shù)知識(shí)的基礎(chǔ)，在教材中起承上啟下的作用。同時(shí)，它體現(xiàn)的數(shù)學(xué)思想與方法在整個(gè)中學(xué)數(shù)學(xué)學(xué)習(xí)中起重要作用。課程目標(biāo)1.理解并掌握同角三角函數(shù)基本關(guān)系式的推導(dǎo)及應(yīng)用．2.會(huì)利用同角三角函數(shù)的基本關(guān)系式進(jìn)行化簡(jiǎn)、求值與恒等式證明．?dāng)?shù)學(xué)學(xué)科素養(yǎng)1.數(shù)學(xué)抽象：理解同角三角函數(shù)基本關(guān)系式；2.邏輯推理： “sin α±cos α”同“sin αcos α”間的關(guān)系；3.數(shù)學(xué)運(yùn)算：利用同角三角函數(shù)的基本關(guān)系式進(jìn)行化簡(jiǎn)、求值與恒等式證明重點(diǎn)：理解并掌握同角三角函數(shù)基本關(guān)系式的推導(dǎo)及應(yīng)用； 難點(diǎn)：會(huì)利用同角三角函數(shù)的基本關(guān)系式進(jìn)行化簡(jiǎn)、求值與恒等式證明．
人教A版高中數(shù)學(xué)必修一正弦函數(shù)、余弦函數(shù)的性質(zhì)教學(xué)設(shè)計(jì)（2）
本節(jié)課是正弦函數(shù)、余弦函數(shù)圖像的繼續(xù)，本課是正弦曲線、余弦曲線這兩種曲線的特點(diǎn)得出正弦函數(shù)、余弦函數(shù)的性質(zhì). 課程目標(biāo)1.了解周期函數(shù)與最小正周期的意義;2.了解三角函數(shù)的周期性和奇偶性;3.會(huì)利用周期性定義和誘導(dǎo)公式求簡(jiǎn)單三角函數(shù)的周期;4.借助圖象直觀理解正、余弦函數(shù)在[0,2π]上的性質(zhì)(單調(diào)性、最值、圖象與x軸的交點(diǎn)等);5.能利用性質(zhì)解決一些簡(jiǎn)單問題. 數(shù)學(xué)學(xué)科素養(yǎng)1.數(shù)學(xué)抽象：理解周期函數(shù)、周期、最小正周期等的含義； 2.邏輯推理： 求正弦、余弦形函數(shù)的單調(diào)區(qū)間；3.數(shù)學(xué)運(yùn)算：利用性質(zhì)求周期、比較大小、最值、值域及判斷奇偶性.4.數(shù)學(xué)建模：讓學(xué)生借助數(shù)形結(jié)合的思想，通過(guò)圖像探究正、余弦函數(shù)的性質(zhì).重點(diǎn)：通過(guò)正弦曲線、余弦曲線這兩種曲線探究正弦函數(shù)、余弦函數(shù)的性質(zhì)； 難點(diǎn)：應(yīng)用正、余弦函數(shù)的性質(zhì)來(lái)求含有cosx,sinx的函數(shù)的單調(diào)性、最值、值域及對(duì)稱性.
兩點(diǎn)間的距離公式教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
一、情境導(dǎo)學(xué)在一條筆直的公路同側(cè)有兩個(gè)大型小區(qū),現(xiàn)在計(jì)劃在公路上某處建一個(gè)公交站點(diǎn)C,以方便居住在兩個(gè)小區(qū)住戶的出行.如何選址能使站點(diǎn)到兩個(gè)小區(qū)的距離之和最小?二、探究新知問題1.在數(shù)軸上已知兩點(diǎn)A、B，如何求A、B兩點(diǎn)間的距離？提示：|AB|＝|xA－xB|.問題2：在平面直角坐標(biāo)系中能否利用數(shù)軸上兩點(diǎn)間的距離求出任意兩點(diǎn)間距離？探究.當(dāng)x1≠x2，y1≠y2時(shí)，|P1P2|＝？請(qǐng)簡(jiǎn)單說(shuō)明理由．提示：可以，構(gòu)造直角三角形利用勾股定理求解．答案：如圖，在Rt △P1QP2中，|P1P2|2＝|P1Q|2＋|QP2|2，所以|P1P2|＝?x2－x1?2＋?y2－y1?2.即兩點(diǎn)P1(x1，y1)，P2(x2，y2)間的距離|P1P2|＝?x2－x1?2＋?y2－y1?2.你還能用其它方法證明這個(gè)公式嗎？2．兩點(diǎn)間距離公式的理解(1)此公式與兩點(diǎn)的先后順序無(wú)關(guān)，也就是說(shuō)公式也可寫成|P1P2|＝?x2－x1?2＋?y2－y1?2.(2)當(dāng)直線P1P2平行于x軸時(shí)，|P1P2|＝|x2－x1|.當(dāng)直線P1P2平行于y軸時(shí)，|P1P2|＝|y2－y1|.
兩條平行線間的距離教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
一、情境導(dǎo)學(xué)前面我們已經(jīng)得到了兩點(diǎn)間的距離公式，點(diǎn)到直線的距離公式，關(guān)于平面上的距離問題，兩條直線間的距離也是值得研究的。思考1：立定跳遠(yuǎn)測(cè)量的什么距離？A.兩平行線的距離 B.點(diǎn)到直線的距離 C. 點(diǎn)到點(diǎn)的距離二、探究新知思考2：已知兩條平行直線l_1,l_2的方程，如何求l_1 〖與l〗_2間的距離？根據(jù)兩條平行直線間距離的含義，在直線l_1上取任一點(diǎn)P（x_0,y_0 ），,點(diǎn)P（x_0,y_0 ）到直線l_2的距離就是直線l_1與直線l_2間的距離，這樣求兩條平行線間的距離就轉(zhuǎn)化為求點(diǎn)到直線的距離。兩條平行直線間的距離1. 定義：夾在兩平行線間的__________的長(zhǎng).公垂線段2. 圖示： 3. 求法：轉(zhuǎn)化為點(diǎn)到直線的距離.1．原點(diǎn)到直線x＋2y－5＝0的距離是( )A．2 B．3 C．2 D．5D [d＝|－5|12＋22＝5.選D.]
兩直線的交點(diǎn)坐標(biāo)教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
1.直線2x+y+8=0和直線x+y-1=0的交點(diǎn)坐標(biāo)是( )A.(-9,-10) B.(-9,10) C.(9,10) D.(9,-10)解析:解方程組{■(2x+y+8=0"," @x+y"-" 1=0"," )┤得{■(x="-" 9"," @y=10"," )┤即交點(diǎn)坐標(biāo)是(-9,10).答案:B 2.直線2x+3y-k=0和直線x-ky+12=0的交點(diǎn)在x軸上,則k的值為( )A.-24 B.24 C.6 D.± 6解析:∵直線2x+3y-k=0和直線x-ky+12=0的交點(diǎn)在x軸上,可設(shè)交點(diǎn)坐標(biāo)為(a,0),∴{■(2a"-" k=0"," @a+12=0"," )┤解得{■(a="-" 12"," @k="-" 24"," )┤故選A.答案:A 3.已知直線l1:ax+y-6=0與l2:x+(a-2)y+a-1=0相交于點(diǎn)P,若l1⊥l2,則點(diǎn)P的坐標(biāo)為 . 解析:∵直線l1:ax+y-6=0與l2:x+(a-2)y+a-1=0相交于點(diǎn)P,且l1⊥l2,∴a×1+1×(a-2)=0,解得a=1,聯(lián)立方程{■(x+y"-" 6=0"," @x"-" y=0"," )┤易得x=3,y=3,∴點(diǎn)P的坐標(biāo)為(3,3).答案:(3,3) 4.求證:不論m為何值,直線(m-1)x+(2m-1)y=m-5都通過(guò)一定點(diǎn). 證明:將原方程按m的降冪排列,整理得(x+2y-1)m-(x+y-5)=0,此式對(duì)于m的任意實(shí)數(shù)值都成立,根據(jù)恒等式的要求,m的一次項(xiàng)系數(shù)與常數(shù)項(xiàng)均等于零,故有{■(x+2y"-" 1=0"," @x+y"-" 5=0"," )┤解得{■(x=9"," @y="-" 4"." )┤
圓的一般方程教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
情境導(dǎo)學(xué)前面我們已討論了圓的標(biāo)準(zhǔn)方程為(x-a)2+(y-b)2=r2,現(xiàn)將其展開可得：x2+y2-2ax-2bx+a2+b2-r2=0.可見,任何一個(gè)圓的方程都可以變形x2+y2+Dx+Ey+F=0的形式.請(qǐng)大家思考一下,形如x2+y2+Dx+Ey+F=0的方程表示的曲線是不是圓?下面我們來(lái)探討這一方面的問題.探究新知例如,對(duì)于方程x^2+y^2-2x-4y+6=0,對(duì)其進(jìn)行配方，得〖(x-1)〗^2+(〖y-2)〗^2=-1,因?yàn)槿我庖稽c(diǎn)的坐標(biāo) (x,y) 都不滿足這個(gè)方程，所以這個(gè)方程不表示任何圖形，所以形如x2+y2+Dx+Ey+F=0的方程不一定能通過(guò)恒等變換為圓的標(biāo)準(zhǔn)方程，這表明形如x2+y2+Dx+Ey+F=0的方程不一定是圓的方程.一、圓的一般方程（1）當(dāng)D2+E2-4F>0時(shí),方程x2+y2+Dx+Ey+F=0表示以(-D/2,-E/2)為圓心,1/2 √(D^2+E^2 "-" 4F)為半徑的圓,將方程x2+y2+Dx+Ey+F=0，配方可得〖(x+D/2)〗^2+(〖y+E/2)〗^2=(D^2+E^2-4F)/4（2）當(dāng)D2+E2-4F=0時(shí),方程x2+y2+Dx+Ey+F=0，表示一個(gè)點(diǎn)(-D/2,-E/2)（3）當(dāng)D2+E2-4F0);
直線的一般式方程教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
解析:當(dāng)a0時(shí),直線ax-by=1在x軸上的截距1/a0,在y軸上的截距-1/a>0.只有B滿足.故選B.答案:B 3．過(guò)點(diǎn)(1,0)且與直線x－2y－2＝0平行的直線方程是( ) A．x－2y－1＝0 B．x－2y＋1＝0C．2x＋y＝2＝0 D．x＋2y－1＝0答案A 解析：設(shè)所求直線方程為x－2y＋c＝0，把點(diǎn)(1,0)代入可求得c＝－1.所以所求直線方程為x－2y－1＝0.故選A.4．已知兩條直線y＝ax－2和3x－(a＋2)y＋1＝0互相平行，則a＝________.答案：1或－3 解析：依題意得：a(a＋2)＝3×1，解得a＝1或a＝－3.5．若方程(m2－3m＋2)x＋(m－2)y－2m＋5＝0表示直線．(1)求實(shí)數(shù)m的范圍；(2)若該直線的斜率k＝1，求實(shí)數(shù)m的值．解析： (1)由m2－3m＋2＝0，m－2＝0，解得m＝2，若方程表示直線，則m2－3m＋2與m－2不能同時(shí)為0，故m≠2.(2)由－?m2－3m＋2?m－2＝1，解得m＝0.
點(diǎn)到直線的距離公式教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
4.已知△ABC三個(gè)頂點(diǎn)坐標(biāo)A(－1,3)，B(－3,0)，C(1,2)，求△ABC的面積S.【解析】由直線方程的兩點(diǎn)式得直線BC的方程為 ＝ ，即x－2y＋3＝0，由兩點(diǎn)間距離公式得|BC|＝ ，點(diǎn)A到BC的距離為d，即為BC邊上的高，d＝ ，所以S＝ |BC|·d＝ ×2 × ＝4，即△ABC的面積為4.5.已知直線l經(jīng)過(guò)點(diǎn)P(0,2),且A(1,1),B(-3,1)兩點(diǎn)到直線l的距離相等,求直線l的方程.解:(方法一)∵點(diǎn)A(1,1)與B(-3,1)到y(tǒng)軸的距離不相等,∴直線l的斜率存在,設(shè)為k.又直線l在y軸上的截距為2,則直線l的方程為y=kx+2,即kx-y+2=0.由點(diǎn)A(1,1)與B(-3,1)到直線l的距離相等,∴直線l的方程是y=2或x-y+2=0.得("|" k"-" 1+2"|" )/√(k^2+1)=("|-" 3k"-" 1+2"|" )/√(k^2+1),解得k=0或k=1.(方法二)當(dāng)直線l過(guò)線段AB的中點(diǎn)時(shí),A,B兩點(diǎn)到直線l的距離相等.∵AB的中點(diǎn)是(-1,1),又直線l過(guò)點(diǎn)P(0,2),∴直線l的方程是x-y+2=0.當(dāng)直線l∥AB時(shí),A,B兩點(diǎn)到直線l的距離相等.∵直線AB的斜率為0,∴直線l的斜率為0,∴直線l的方程為y=2.綜上所述,滿足條件的直線l的方程是x-y+2=0或y=2.
圓的標(biāo)準(zhǔn)方程教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
(1)幾何法它是利用圖形的幾何性質(zhì),如圓的性質(zhì)等,直接求出圓的圓心和半徑,代入圓的標(biāo)準(zhǔn)方程,從而得到圓的標(biāo)準(zhǔn)方程.(2)待定系數(shù)法由三個(gè)獨(dú)立條件得到三個(gè)方程,解方程組以得到圓的標(biāo)準(zhǔn)方程中三個(gè)參數(shù),從而確定圓的標(biāo)準(zhǔn)方程.它是求圓的方程最常用的方法,一般步驟是:①設(shè)——設(shè)所求圓的方程為(x-a)2+(y-b)2=r2;②列——由已知條件,建立關(guān)于a,b,r的方程組;③解——解方程組,求出a,b,r;④代——將a,b,r代入所設(shè)方程,得所求圓的方程.跟蹤訓(xùn)練1．已知△ABC的三個(gè)頂點(diǎn)坐標(biāo)分別為A(0,5)，B(1，－2)，C(－3，－4)，求該三角形的外接圓的方程．[解] 法一：設(shè)所求圓的標(biāo)準(zhǔn)方程為(x－a)2＋(y－b)2＝r2.因?yàn)锳(0,5)，B(1,－2)，C(－3,－4)都在圓上，所以它們的坐標(biāo)都滿足圓的標(biāo)準(zhǔn)方程，于是有?0－a?2＋?5－b?2＝r2，?1－a?2＋?－2－b?2＝r2，?－3－a?2＋?－4－b?2＝r2.解得a＝－3，b＝1，r＝5.故所求圓的標(biāo)準(zhǔn)方程是(x＋3)2＋(y－1)2＝25.
圓與圓的位置關(guān)系教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
1.兩圓x2+y2-1=0和x2+y2-4x+2y-4=0的位置關(guān)系是( )A.內(nèi)切 B.相交 C.外切 D.外離解析:圓x2+y2-1=0表示以O(shè)1(0,0)點(diǎn)為圓心,以R1=1為半徑的圓.圓x2+y2-4x+2y-4=0表示以O(shè)2(2,-1)點(diǎn)為圓心,以R2=3為半徑的圓.∵|O1O2|=√5,∴R2-R1<|O1O2|<R2+R1,∴圓x2+y2-1=0和圓x2+y2-4x+2y-4=0相交.答案:B2.圓C1:x2+y2-12x-2y-13=0和圓C2:x2+y2+12x+16y-25=0的公共弦所在的直線方程是 . 解析:兩圓的方程相減得公共弦所在的直線方程為4x+3y-2=0.答案:4x+3y-2=03.半徑為6的圓與x軸相切,且與圓x2+(y-3)2=1內(nèi)切,則此圓的方程為( )A.(x-4)2+(y-6)2=16 B.(x±4)2+(y-6)2=16C.(x-4)2+(y-6)2=36 D.(x±4)2+(y-6)2=36解析:設(shè)所求圓心坐標(biāo)為(a,b),則|b|=6.由題意,得a2+(b-3)2=(6-1)2=25.若b=6,則a=±4;若b=-6,則a無(wú)解.故所求圓方程為(x±4)2+(y-6)2=36.答案:D4.若圓C1:x2+y2=4與圓C2:x2+y2-2ax+a2-1=0內(nèi)切,則a等于 . 解析:圓C1的圓心C1(0,0),半徑r1=2.圓C2可化為(x-a)2+y2=1,即圓心C2(a,0),半徑r2=1,若兩圓內(nèi)切,需|C1C2|=√(a^2+0^2 )=2-1=1.解得a=±1. 答案:±1 5. 已知兩個(gè)圓C1:x2+y2=4,C2:x2+y2-2x-4y+4=0,直線l:x+2y=0,求經(jīng)過(guò)C1和C2的交點(diǎn)且和l相切的圓的方程.解:設(shè)所求圓的方程為x2+y2+4-2x-4y+λ(x2+y2-4)=0,即(1+λ)x2+(1+λ)y2-2x-4y+4(1-λ)=0.所以圓心為 1/(1+λ),2/(1+λ) ,半徑為1/2 √((("-" 2)/(1+λ)) ^2+(("-" 4)/(1+λ)) ^2 "-" 16((1"-" λ)/(1+λ))),即|1/(1+λ)+4/(1+λ)|/√5=1/2 √((4+16"-" 16"(" 1"-" λ^2 ")" )/("(" 1+λ")" ^2 )).解得λ=±1,舍去λ=-1,圓x2+y2=4顯然不符合題意,故所求圓的方程為x2+y2-x-2y=0.
直線的點(diǎn)斜式方程教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
【答案】B [由直線方程知直線斜率為3，令x＝0可得在y軸上的截距為y＝－3.故選B.]3．已知直線l1過(guò)點(diǎn)P(2,1)且與直線l2：y＝x＋1垂直，則l1的點(diǎn)斜式方程為________．【答案】y－1＝－(x－2) [直線l2的斜率k2＝1，故l1的斜率為－1，所以l1的點(diǎn)斜式方程為y－1＝－(x－2)．]4．已知兩條直線y＝ax－2和y＝(2－a)x＋1互相平行，則a＝________. 【答案】1 [由題意得a＝2－a，解得a＝1.]5.無(wú)論k取何值,直線y-2=k(x+1)所過(guò)的定點(diǎn)是 . 【答案】(-1,2)6．直線l經(jīng)過(guò)點(diǎn)P(3,4)，它的傾斜角是直線y＝3x＋3的傾斜角的2倍，求直線l的點(diǎn)斜式方程．【答案】直線y＝3x＋3的斜率k＝3，則其傾斜角α＝60°，所以直線l的傾斜角為120°.以直線l的斜率為k′＝tan 120°＝－3.所以直線l的點(diǎn)斜式方程為y－4＝－3(x－3)．
直線與圓的位置關(guān)系教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
切線方程的求法1.求過(guò)圓上一點(diǎn)P(x0,y0)的圓的切線方程:先求切點(diǎn)與圓心連線的斜率k,則由垂直關(guān)系,切線斜率為-1/k,由點(diǎn)斜式方程可求得切線方程.若k=0或斜率不存在,則由圖形可直接得切線方程為y=b或x=a.2.求過(guò)圓外一點(diǎn)P(x0,y0)的圓的切線時(shí),常用幾何方法求解設(shè)切線方程為y-y0=k(x-x0),即kx-y-kx0+y0=0,由圓心到直線的距離等于半徑,可求得k,進(jìn)而切線方程即可求出.但要注意,此時(shí)的切線有兩條,若求出的k值只有一個(gè)時(shí),則另一條切線的斜率一定不存在,可通過(guò)數(shù)形結(jié)合求出.例3 求直線l:3x+y-6=0被圓C:x2+y2-2y-4=0截得的弦長(zhǎng).思路分析:解法一求出直線與圓的交點(diǎn)坐標(biāo),解法二利用弦長(zhǎng)公式,解法三利用幾何法作出直角三角形,三種解法都可求得弦長(zhǎng).解法一由{■(3x+y"-" 6=0"," @x^2+y^2 "-" 2y"-" 4=0"," )┤得交點(diǎn)A(1,3),B(2,0),故弦AB的長(zhǎng)為|AB|=√("(" 2"-" 1")" ^2+"(" 0"-" 3")" ^2 )=√10.解法二由{■(3x+y"-" 6=0"," @x^2+y^2 "-" 2y"-" 4=0"," )┤消去y,得x2-3x+2=0.設(shè)兩交點(diǎn)A,B的坐標(biāo)分別為A(x1,y1),B(x2,y2),則由根與系數(shù)的關(guān)系,得x1+x2=3,x1·x2=2.∴|AB|=√("(" x_2 "-" x_1 ")" ^2+"(" y_2 "-" y_1 ")" ^2 )=√(10"[(" x_1+x_2 ")" ^2 "-" 4x_1 x_2 "]" ┴" " )=√(10×"(" 3^2 "-" 4×2")" )=√10,即弦AB的長(zhǎng)為√10.解法三圓C:x2+y2-2y-4=0可化為x2+(y-1)2=5,其圓心坐標(biāo)(0,1),半徑r=√5,點(diǎn)(0,1)到直線l的距離為d=("|" 3×0+1"-" 6"|" )/√(3^2+1^2 )=√10/2,所以半弦長(zhǎng)為("|" AB"|" )/2=√(r^2 "-" d^2 )=√("(" √5 ")" ^2 "-" (√10/2) ^2 )=√10/2,所以弦長(zhǎng)|AB|=√10.
直線的兩點(diǎn)式方程教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊(cè)
解析：①過(guò)原點(diǎn)時(shí)，直線方程為y＝－34x.②直線不過(guò)原點(diǎn)時(shí)，可設(shè)其方程為xa＋ya＝1，∴4a＋－3a＝1，∴a＝1.∴直線方程為x＋y－1＝0.所以這樣的直線有2條，選B.答案：B4.若點(diǎn)P(3,m)在過(guò)點(diǎn)A(2,-1),B(-3,4)的直線上,則m= . 解析:由兩點(diǎn)式方程得,過(guò)A,B兩點(diǎn)的直線方程為(y"-(-" 1")" )/(4"-(-" 1")" )=(x"-" 2)/("-" 3"-" 2),即x+y-1=0.又點(diǎn)P(3,m)在直線AB上,所以3+m-1=0,得m=-2.答案:-2 5.直線ax+by=1(ab≠0)與兩坐標(biāo)軸圍成的三角形的面積是 . 解析:直線在兩坐標(biāo)軸上的截距分別為1/a 與 1/b,所以直線與坐標(biāo)軸圍成的三角形面積為1/(2"|" ab"|" ).答案:1/(2"|" ab"|" )6.已知三角形的三個(gè)頂點(diǎn)A(0,4)，B(－2,6)，C(－8,0)．(1)求三角形三邊所在直線的方程；(2)求AC邊上的垂直平分線的方程．解析(1)直線AB的方程為y－46－4＝x－0－2－0，整理得x＋y－4＝0；直線BC的方程為y－06－0＝x＋8－2＋8，整理得x－y＋8＝0；由截距式可知，直線AC的方程為x－8＋y4＝1，整理得x－2y＋8＝0.(2)線段AC的中點(diǎn)為D(－4,2)，直線AC的斜率為12，則AC邊上的垂直平分線的斜率為－2，所以AC邊的垂直平分線的方程為y－2＝－2(x＋4)，整理得2x＋y＋6＝0.
新人教版高中英語(yǔ)必修3Unit 3 Diverse Cultures-Listening &Speaking＆Talking教學(xué)設(shè)計(jì)
1. In Picture 1 and Picture 2, where do you think they are from? How do you know?From their wearings, we can know they are from ethnic minority of China--- Miao and Dong.Picture 1, they are playing their traditional instrument lusheng in their traditional costumes.Picture 2. the girls are Miao because they wear their traditional costumes and silver accessory.2. In Picture 3, can you find which village it is? What time is it in the picture?It is Dong village. It is at night. Step 2 While-listeningJustin met a new friend while traveling in Guizhou. Listen to their conversation and complete the summaries below.Part 1Justin and Wu Yue watched some Miao people play the lusheng. The instrument has a history of over 3,000 years and it is even mentioned in the oldest collection of Chinese poetry. Then they watched the lusheng dance. Justin wanted to buy some hand-made silver/traditional accessories as souvenirs. He was told that the price will depend on the percentage of silver. Part 2They will go to a pretty Dong minority village called Zhaoxing. they will see the drum towers and the wind and rain bridges. They may also see a performance of the Grand Song of the Dong people.Step 3 Post-listening---TalkingWork in groups. Imagine Justin is telling some friends about his trip to Guizhou. One of you is Justin and the rest of you are his friends. Ask Justin questions about his trip and experience. The following expressions may help you.
新人教版高中英語(yǔ)必修3Unit 3 Diverse Cultures-Reading and Thinking教學(xué)設(shè)計(jì)
Discuss these questions in groups.Q1: Have you ever been to a place that has a diverse culture ? What do you think about the culture diversity ?One culturally diverse place that I have been to is Harbin, the capital city of Heilongjiang Province. I went there last year with my family to see the Ice and Snow Festival, and I was amazed at how the culture as different to most other Chinese cities. There is a big Russian influence there, with beautiful Russian architecture and lots of interesting restaurants. I learnt that Harbin is called “the Oriental Moscow” and that many Russians settled there to help build the railway over 100 years ago.Q2: What are the benefits and challenges of cultural diversity ?The benefits: People are able to experience a wide variety of cultures, making their lives more interesting, and it can deepen the feelings for our national culture, it is also helpful for us to learn about other outstanding culture, which helps improve the ability to respect others. The challenges: People may have trouble communicating or understanding each other, and it may lead to disappearance of some civilizations and even make some people think “The western moon is rounder than his own.”Step 7 Post reading---RetellComplete the passage according to the text.Today, I arrived back in San Francisco, and it feels good (1) _____(be) back in the city again. The city succeeded in (2)_________ (rebuild) itself after the earthquake that (3)________ (occur) in 1906, and I stayed in the Mission District, enjoying some delicious noodles mixed with cultures. In the afternoon, I headed to a local museum (4)____ showed the historical changes in California. During the gold rush, many Chinese arrived, and some opened up shops and restaurants in Chinatown to earn a (5)_____ (live). Many others worked on (6)______ (farm), joined the gold rush, or went to build the railway that connected California to the east. The museum showed us (7)____ America was built by immigrants from (8)________ (difference) countries and cultures. In the evening, I went to Chinatown, and ate in a Cantonese restaurant that served food on (9)________(beauty) china plates. Tomorrow evening, I’m going to (10)__ jazz bar in the Richmond District. 答案：1. to be 2. rebuilding 3. occurred 4. that 5.living6. farms 7.how 8. different 9. beautiful 10. a
新人教版高中英語(yǔ)必修3Unit 4 Space Exploration-Discovering Useful Structure教學(xué)設(shè)計(jì)
The theme of the section is “Describe space facts and efforts to explore space”. Infinitives are one of non-finite verbs, as the subjects, objects, predicative, attributes and adverbials. This unit is about space exploration, which is a significant scientific activity, so every scientific activity has strong planning. Therefore, using the infinitives to show its purpose, explanations or restrictions is the best choice.1. Learn the structure, functions and features of infinitives.2. Learn to summarize some rules about infinitives to show purpose and modify.3. Learn to use infinitives in oral and writing English. 1. Learn the structure, functions and features of infinitives.2. Learn to summarize some rules about infinitives to show purpose and modify.3. Learn to use use infinitives in oral and writing English.Step 1 Lead in---Pair workLook at the following sentences and focus on the italicized infinitives. In pairs, discuss their functions. 1. I trained for a long time to fly airplanes as a fighter pilot..(作目的狀語(yǔ))2. As we all know, an astronaut needs to be healthy and calm in order to work in space..(作目的狀語(yǔ))3. First of all, you must be intelligent enough to get a related college degree..(作目的狀語(yǔ))4. Some scientist were determined to help humans realise their dream to explore space..(作定語(yǔ))5. On 12 April 1961, Yuri Gagarin became the first person in the world to go into space..(作定語(yǔ))Summary:1. 不定式的結(jié)構(gòu)：to+do原形。2. 分析上面的句子，我們知道在描述太空探索時(shí)，動(dòng)詞不定式不僅可以用來(lái)表目的，還可以用來(lái)作定語(yǔ)，表修飾。
新人教版高中英語(yǔ)必修3Unit 4 Space Exploration-Reading and Thinking教學(xué)設(shè)計(jì)二
The theme of this unit focuses on “space exploration.” Students will learn about the training and experience needed to become an astronaut. The text is mainly about the development of space exploration. On the one hand, the text helps students to have a good understanding about the great feats humans have achieved, on the other hand, they will further understand the contributions that we Chinese have achieved, and feel confident and proud about our homeland and strengthen their love for our country. The teacher should instruct students to aim high and study harder to make great progress in the space career if possible.1. Read about the development and value of space exploration.2. Explore the mysteries of the universe and the achievements in space exploration.3. Skillfully use the vocabulary of this text to cultivate self-study ability 4. Develop cooperative learning ability through discussion.1. Enable the Ss to talk about the development and value of space exploration.2. Guide the Ss to summarize the main idea of each paragraph as well as the main idea of the text.3. Help Ss comprehend the main reasons for space exploration. Multi-media, textbook, notebooks.Step 1: Warming up and predictionLook at the title and the pictures of the text and predict what the text will be about?2. What are the main reasons for space exploration?
新人教版高中英語(yǔ)必修3Unit 4 Space Exploration-Reading and Thinking教學(xué)設(shè)計(jì)一
Q4: What is the function of the International exploration ?Having astronauts from different countries on boardQ5: What can you learn from Para 4 ?China has made great achievements in exploring spaceQ6: What is the attitude to the space exploration ?SupportiveStep 6 Post reading---RetellPeople have always wanted to learn more about space. Before the mid-20th century, most people felt (1)_________ (travel) into space was an impossible dream. However, (2)____ the help of scientists, peoplesucceeded in realizing their dream (3) _________ (explore) space. On 4 October 1957, the Sputnik 1 satellite (4) ____________(launch) by the USSR. (5) ________________ scientists try to make sure nothing goes wrong, accidents can still happen. These disasters made everyone(6)___________(disappoint), but people still believe in the importance of (7) ________(carry) on space exploration. In 2003, China became the third country to (8)_____________ (independent) send humans into space. Then Shenzhou 6 and 7 completed (9)____ second manned orbit and the first Chinese spacewalk. In spite of the difficulties, scientists hope future (10)__________ (discovery) will not only enable us to understand the universe but also help us survive well into the future.Answers: 1. travelling 2. with 3. to explore 4. was launched 5. Although6. disappointed 7. carrying 8. independently 9. a 10. discoveriesStep 6 Post reading---Critical thinkingQ1: What do you think of the space exploration ? I think it is beneficial to us. Through further study of space, people will make full use of it in the future, such as the space experiments by Wang Yaping in Tian Gong 1.Q2: If you are determined to be an astronaut, what should you prepare at present ?First of all, I should study hard to get a related college degree. Besides, I must keep mental and physical healthy.Step 7. HomeworkTry to summarize the structure of the article by a mind map.
新人教版高中英語(yǔ)必修3Unit 4 Space Exploration-Reading For Writing教學(xué)設(shè)計(jì)一
另一方面，其余的人反對(duì)這個(gè)計(jì)劃，因?yàn)樗赡軙?huì)導(dǎo)致一些不好的影響。7.I hold the belief that space exploration not only enable us to understand how the universe began but also help us survived well into the future.我堅(jiān)信探索太空不僅能夠使我們了解宇宙的起源而且能夠幫助我們更好地走進(jìn)未來(lái)。8.I think we should spend more time and money exploring space so as to provide new and better solutions to people's shortterm and longterm problems.為了給人類的短期和長(zhǎng)期問題提供更新和更好的解決方法，我認(rèn)為我們應(yīng)該花更多的時(shí)間和金錢來(lái)探索太空。9．From my point of view，it is wrong of young people to depend on their telephones too much，which may do harm to both their physical and mental health.在我看來(lái)，年輕人過(guò)度依賴手機(jī)是不對(duì)的，因?yàn)樗鼈兛赡軙?huì)對(duì)他們的身心健康都有害。最近你班同學(xué)就“人類是否應(yīng)該進(jìn)行宇宙探索”這個(gè)問題進(jìn)行了激烈的討論。有人認(rèn)為，探索宇宙不僅讓人類更好地了解宇宙的發(fā)展，還可以用來(lái)指導(dǎo)農(nóng)業(yè)生產(chǎn)，以及把一些探索太空的高新技術(shù)用于現(xiàn)實(shí)生活；也有一些人認(rèn)為探索太空花掉了大量的人力物力；影響了人們的生活水平。請(qǐng)你根據(jù)以下情況寫一篇報(bào)告并發(fā)表自己的觀點(diǎn)。注意：1.寫作內(nèi)容應(yīng)包括以上全部要點(diǎn)，可適當(dāng)發(fā)揮，使上下文連貫；