Question

求由方程所确定的隐函数的导数dy/dx? y=cos(x+y)

Answer 1

y=coa(x+y)

dy/dx=-sin(x+y)·(1+dy/dx)

dy/dx=-sin(x+y)-sin(x+y)·dy/dx

[1+sin(x+y)]dy/dx=-sin(x+y)

dy/dx=-sin(x+y)/[1+sin(x+y)]