lim & ltx→0+>f(x)= lim & lt； X→0+>A+bx = f(0) = a, then a = 1.

The function is differentiable lim < x → 0->; [f(x)-f(0)]/(x-0)= lim & lt； x→0-& gt； (e^x- 1)/x = 1，

lim & ltx→0+>[f(x)-f(0)]/(x-0)= lim & lt； X→0+>Bx/x = b, then b = 1.

(2) The derivative of f (x) at x = 0 is f'(0) = 1, that is, the tangent slope is 1 and the tangent equation is y = x,

The normal equation is y = -x x x.