y=x/(√a²-x²),求dy/dx!
问题描述：
y=x/(√a²-x²),求dy/dx!
答
dy/dx=[x/√(a²-x²)]'
=[√(a²-x²)+x²/√(a²-x²)]/(a²-x²)
=[(a²-x²)+x²]/(a²-x²)^(3/2)
=a²/(a²-x²)^(3/2).