24/12/261函数函数y=Asin(y=Asin(x+x+))的图象的图象(2)(2)数学系:危婷24/12/262sinyx
y=Asinxsinyx
sinyxsinyx
sin()yx⒈⒉⒊二、24/12/263例用五点法作函数的图象3sin(2)3yxxRy=3sin(2x+)3xyo6531263127-324/12/264y=3sin(2x+)324/12/2651-12-2oxy3-326536335y=sin(2x+)②3y=sinxy=sin(x+)①3y=3sin(2x+)③3方法1:先平移后伸缩24/12/266函数y=sinxy=sin(x+)的图象3(3)横坐标不变纵坐标伸长到原来的3倍y=3sin(2x+)的图象3y=sin(2x+)的图象3(1)向左平移3纵坐标不变(2)横坐标缩短到原来的倍2124/12/267y=Sin(x+)的图象函数y=Sinxy=Sin(x+)的图象(3)纵坐标伸长(A>1)或缩短(0