图象由f(x)=sinx 变为f(x)=sin(2x-π/4)
(1)①向右平移π/4个单位f(x)=sin(x-π/4)
②横坐标变为原来的1/2f(x)=sin(2x-π/4)
(2)①f(x)=sinx横坐标变为原来的1/2f(x)=sin(2x)
②向右平移π/8个单位f(x)=sin[2(x-π/8)]=sin(2x-π/4)
先伸缩再平移,平移的距离是|φ/ω|
先平移再伸缩,平移的距离|φ|
关于:平移伸缩只对x
①f(x)=sin(x-π/4) 横坐标变为原来的1/2 :f(x)=sin(2x-π/4)
若f(x)=sin2(x-π/4)就错了
②f(x)=sin(2x) 向右平移π/8个单位:f(x)=sin[2(x-π/8)]=sin(2x-π/4)
若f(x)=sin(2x-π/8)就错了