分别把t，和x带进去就行了啊。第一个y(x)=10cos(16π-π/2-π/10*x)=10cos(-π/2-π/10*π）=-10sin(π/10*x)第二个y(t)=10cos(8πt-π/2-π/2)=10cos(8πt-π）=-10cos(8πt)
