역쇄법칙을 사용하여 미분계수 구하기.(연습) 밑바닥 153p 참고 class Function1: def forward(self, x): z = x - 2 return z def backward(self, dy_dz): self.dy_dx = 1 self.dy_dx *= dy_dz # chain rule return self.dy_dx class Function2: def forward(self, z): self.y = 2*(z**2) return self.y def backward(self): return self.y * 4 class FunctionUnion: def __init__(self): print(f'f(x) = 2*(x - 2)**2\n') self.f1 = Function1() self.f..