【正文】
圖3(三)、解決方程與不等式的問題處理方程問題時(shí),把方程的根的問題看作兩個(gè)函數(shù)圖像的交點(diǎn)問題;處理不等式時(shí),從題目的條件與結(jié)論出發(fā),聯(lián)系相關(guān)函數(shù),著重分析其幾何意義,從圖形上找出解題的思路。分析:在分析此題時(shí), 要引導(dǎo)學(xué)生利用數(shù)形結(jié)合思想, 在同一坐標(biāo)系中, 先分別畫出 y = 4 x, y = x + 1, y = (5 x)的圖像,如圖2。如圖 1, 由圖我們不難得出A∩B=[0,3]。下面就數(shù)形結(jié)合思想在集合問題、函數(shù)、方程、不等式、線性規(guī)劃、數(shù)列及解析幾何中的應(yīng)用做一個(gè)系統(tǒng)的分析。 作為一種數(shù)學(xué)思想方法,數(shù)形結(jié)合的應(yīng)用大致又可分為兩種基本形式,一是“形”的問題轉(zhuǎn)化為用數(shù)量關(guān)系去解決,運(yùn)用代數(shù)、三角知識(shí)進(jìn)行討論,它往往把技巧性極強(qiáng)的推理論證轉(zhuǎn)化可具體操作的代數(shù)運(yùn)算,很好的起到化難為易的作用。中學(xué)數(shù)學(xué)研究的對(duì)象可分為兩大部分,一部分是數(shù),一部分是形,但數(shù)與形是有聯(lián)系的,這個(gè)聯(lián)系稱之為數(shù)形結(jié)合或形數(shù)結(jié)合。中學(xué)數(shù)學(xué)教學(xué)中處處滲透著基本數(shù)學(xué)思想,如果能使它落實(shí)到學(xué)生學(xué)習(xí)和運(yùn)用數(shù)學(xué)的思維活動(dòng)上,它就能在發(fā)展學(xué)生的數(shù)學(xué)能力方面發(fā)揮出一種方法論的功能。s deficiency by learning from others strong points mutually in short”. Counts the shape union as one mon mathematical method, has municated the algebra, the triangle and the geometry inner link. On one hand, with the aid in the graph nature may make many abstract mathematics concepts and the stoichiometric relation visualization and simplification, for the human by the intuition enlightenment. On the other hand, transforming the graph question as the algebra question, obtains the precise conclusion. Therefore, counts the shape union not to take one problem solving method merely, but should take one very important mathematics thinking method, it may expand students39。一方面,借助于圖形的性質(zhì)可以將許多抽象的數(shù)學(xué)概念和數(shù)量關(guān)系形象化、簡(jiǎn)單化,給人以直覺的啟示。 數(shù)形結(jié)合作為一種常見的數(shù)學(xué)方法, 溝通了代數(shù)、三角與幾何的內(nèi)在聯(lián)系。關(guān)鍵詞: 數(shù)形結(jié)合思想;直觀;數(shù)學(xué)教學(xué);應(yīng)用Discusses the number shape union thought shallowly in the teaching applicationWang yang(Department of Mathematics, Hefei Normal University)ABSTRACTCounts the shape union is unifying the question stoichiometric relation and the space form to inspect, accor