x=a(t-sint),y=a(1-cost),请构造关于x,y的二元函数f(x,y),使得f(x,y)
问题描述：
x=a(t-sint),y=a(1-cost),请构造关于x,y的二元函数f(x,y),使得f(x,y)
答
4a[1-cos(t/2)]=8a[sin(t/4)]^21-cost=2[sin(t/2)]^2sint=2sin(t/2)cos(t/2)tan(t/2)=(1-cost)/sintcot(t/2)=sint/(1-cost)[sin(t/2)]^2=1/[1+[cot(t/2)]^2]=(1-cost)^2/[(sint)^2+(1-cost)^2](1-cost)^2/[[(t-sint)...