描點(diǎn)法畫(huà)函數(shù)y=4x+cos(77x+132)的性質(zhì)及其圖像主要內(nèi)容：本文根據(jù)余弦等函數(shù)的有關(guān)性質(zhì)，介紹通過(guò)描點(diǎn)法畫(huà)出三角函數(shù)y=4x+cos(77x+132)在區(qū)間[-EQ\F(4π+132,77),EQ\F(4π-132,77)]區(qū)間上圖像示意圖的主要過(guò)程與步驟?！?函數(shù)的定義域根據(jù)函數(shù)的特征，函數(shù)是一次函數(shù)y?=4x和余弦函數(shù)y?=cos(77x+132)的和函數(shù)，且二者的定義域?yàn)槿w實(shí)數(shù)，所以其和函數(shù)的定義域也為全體實(shí)數(shù)，即為:(-∞，+∞)?！?函數(shù)描點(diǎn)思路由于函數(shù)y=4x+cos(77x+132)含有三角余弦函數(shù)，三角函數(shù)具有周期性值，故描點(diǎn)以三角函數(shù)為中心函數(shù)，分別取三角函數(shù)值為0，±1以及45°角時(shí)的取值為本例函數(shù)的特征點(diǎn)?！?函數(shù)的部分點(diǎn)圖本處以區(qū)間[-EQ\F(4π+132,77),EQ\F(4π-132,77)]為例，描點(diǎn)列為：x-1.877-1.867-1.857-1.847-1.83777x+132-4π-15π/4-7π/2-13π/4-3πcos(77x+132)10.710-0.71-14x-7.51-7.47-7.43-7.39-7.35y-6.51-6.76-7.43-8.10-8.35x-1.826-1.816-1.806-1.796-1.78677x+132-11π/4-5π/2-9π/4-2π-7π/4cos(77x+132)-0.7100.7110.714x-7.30-7.26-7.22-7.18-7.14y-8.0-7.3-6.5-6.2-6.4x-1.775-1.765-1.755-1.745-1.73577x+132-3π/2-5π/4-π-3π/4-π/2cos(77x+132)0-0.71-1-0.7104x-7.10-7.06-7.02-6.98-6.94y-7.1-7.8-8.0-7.7-6.9x-1.724-1.714-1.704-1.694-1.684-1.67377x+132-π/40π/4π/23π/4πcos(77x+132)0.7110.7100.71-14x-6.90-6.86-6.82-6.78-6.74-6.69y-6.2-5.9-6.1-6.8-7.4-7.7x-1.663-1.653-1.643-1.633-1.622-1.61277x+1325π/43π/27π/42π9π/45π/2cos(77x+132)-0.7100.7110.7104x-6.65-6.61-6.57-6.53-6.49-6.45y-7.4-6.6-5.9-5.5-5.8-6.4x-1.602-1.592-1.582-1.571-1.561-1.55177x+13211/4π3π13π/47π/215π/44πcos(77x+132)-0.71-1-0.7100.7114x-6.41-6.37-6.33-6.28-6.24-6.20y-7.1-7.4-7.0-6.3-5.5-5.2※.函數(shù)的示意圖y=4x+cos(77x+132) y (-1.551,-5.2)(-1.714,-5.9) x