描點(diǎn)法畫函數(shù)y=113x+cos(163x+217)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)，介紹通過描點(diǎn)法畫出三角函數(shù)y=113x+cos(163x+217)在區(qū)間[-EQ\F(4π+217,163),EQ\F(4π-217,163)]區(qū)間上圖像示意圖的主要過程與步驟?！?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?=113x和余弦函數(shù)y?=cos(163x+217)的和函數(shù)，且二者的定義域為全體實數(shù)，所以其和函數(shù)的定義域也為全體實數(shù)，即為:(-∞，+∞)。※.函數(shù)描點(diǎn)思路由于函數(shù)y=113x+cos(163x+217)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+217,163),EQ\F(4π-217,163)]為例，描點(diǎn)列為：x-1.408-1.404-1.399-1.394-1.389163x+217-4π-15π/4-7π/2-13π/4-3πcos(163x+217)10.710-0.71-1113x-159.10-158.65-158.09-157.52-156.96y-158.10-157.94-158.09-158.23-157.96x-1.384-1.379-1.375-1.370-1.365163x+217-11π/4-5π/2-9π/4-2π-7π/4cos(163x+217)-0.7100.7110.71113x-156.39-155.83-155.38-154.81-154.25y-157.1-155.8-154.7-153.8-153.5x-1.360-1.355-1.351-1.346-1.341163x+217-3π/2-5π/4-π-3π/4-π/2cos(163x+217)0-0.71-1-0.710113x-153.68-153.12-152.66-152.10-151.53y-153.7-153.8-153.7-152.8-151.5x-1.336-1.331-1.326-1.322-1.317-1.312163x+217-π/40π/4π/23π/4πcos(163x+217)0.7110.7100.71-1113x-150.97-150.40-149.84-149.39-148.82-148.26y-150.3-149.4-149.1-149.4-149.5-149.3x-1.307-1.302-1.298-1.293-1.288-1.283163x+2175π/43π/27π/42π9π/45π/2cos(163x+217)-0.7100.7110.710113x-147.69-147.13-146.67-146.11-145.54-144.98y-148.4-147.1-146.0-145.1-144.8-145.0x-1.278-1.273-1.269-1.264-1.259-1.254163x+21711/4π3π13π/47π/215π/44πcos(163x+217)-0.71-1-0.7100.711113x-144.41-143.85-143.40-142.83-142.27-141.70y-145.1-144.8-144.1-142.8-141.6-140.7※.函數(shù)的示意圖y=113x+cos(163x+217) y (-1.254,-140.7)(-1.331,-149.4) x