描点法画形如三角余弦函数y=x+cosax+b图像示意图过程C8

描点法画函数y=67x+cos(79x+84)的性质及其图像主要内容：本文根据余弦等函数的有关性质，介绍通过描点法画出三角函数y=67x+cos(79x+84)在区间[-EQ\F(4π+84,79),EQ\F(4π-84,79)]区间上图像示意图的主要过程与步骤。※.函数的定义域根据函数的特征，函数是一次函数y₁=67x和余弦函数y₂=cos(79x+84)的和函数，且二者的定义域为全体实数，所以其和函数的定义域也为全体实数，即为:(-∞，+∞)。※.函数描点思路由于函数y=67x+cos(79x+84)含有三角余弦函数，三角函数具有周期性值，故描点以三角函数为中心函数，分别取三角函数值为0，±1以及45°角时的取值为本例函数的特征点。※.函数的部分点图本处以区间[-EQ\F(4π+84,79),EQ\F(4π-84,79)]为例，描点列为：x-1.222-1.212-1.202-1.193-1.18379x+84-4π-15π/4-7π/2-13π/4-3πcos(79x+84)10.710-0.71-167x-81.87-81.20-80.53-79.93-79.26y-80.87-80.49-80.53-80.64-80.26x-1.173-1.163-1.153-1.143-1.13379x+84-11π/4-5π/2-9π/4-2π-7π/4cos(79x+84)-0.7100.7110.7167x-78.59-77.92-77.25-76.58-75.91y-79.3-77.9-76.5-75.6-75.2x-1.123-1.113-1.103-1.093-1.08379x+84-3π/2-5π/4-π-3π/4-π/2cos(79x+84)0-0.71-1-0.71067x-75.24-74.57-73.90-73.23-72.56y-75.2-75.3-74.9-73.9-72.6x-1.073-1.063-1.053-1.043-1.033-1.02479x+84-π/40π/4π/23π/4πcos(79x+84)0.7110.7100.71-167x-71.89-71.22-70.55-69.88-69.21-68.61y-71.2-70.2-69.8-69.9-69.9-69.6x-1.014-1.004-0.994-0.984-0.974-0.96479x+845π/43π/27π/42π9π/45π/2cos(79x+84)-0.7100.7110.71067x-67.94-67.27-66.60-65.93-65.26-64.59y-68.6-67.3-65.9-64.9-64.5-64.6x-0.954-0.944-0.934-0.924-0.914-0.90479x+8411/4π3π13π/47π/215π/44πcos(79x+84)-0.71-1-0.7100.71167x-63.92-63.25-62.58-61.91-61.24-60.57y-64.6-64.2-63.3-61.9-60.5-59.6※.函数的示意图y=67x+cos(79x+84) y (-0.904,-59.6)(-1.063,-70.2) x