Can't put the max and min in my python code for my graphs, using matplotlib

i’m trying to graphic two functions of cosine, which both have different amplitude. I want to mark the max, min and where both touch zero, in the graphic. First im trying to mark the max, but this doesn’t seems to work. I have search many codes in stackoverflow and for some reason, when I compile the code it starts getting errors. Can anyone help me, finding max and min of my graphic please.

Here is my code:

import matplotlib
import numpy as np 
import matplotlib.pyplot as plt

def h(X):
        return (10*(np.cos(((120*(np.pi))*x)+((np.pi/6)))))

def g(x):
        return (5*(np.cos(((120*(np.pi))*x)-((np.pi/6)))))

x = np.linspace(0, 0.05, 1000)


plt.ylabel("Voltaje (V)")
plt.xlabel("Tiempo (s)")


plt.grid(True)

def annot_max(x,y, ax=None):
    xmax = x[np.argmax(y)]
    ymax = y.max()
    text= "x={:.3f}, y={:.3f}".format(xmax, ymax)
    if not ax:
        ax=plt.gca()
    bbox_props = dict(boxstyle="square,pad=0.3", fc="w", ec="k", lw=0.72)
    arrowprops=dict(arrowstyle="->",connectionstyle="angle,angleA=0,angleB=60")
    kw = dict(xycoords='data',textcoords="data",
              arrowprops=arrowprops, bbox=bbox_props, ha="left", va="top")
    ax.annotate(text, xy=(xmax, ymax), xytext=(xmax+.5,ymax+5), **kw)

#plt.annotate("maximo de grafica 1", xy=(2,1), xytext=(3,1.5) , arrowprops=dict(facecolor="black", shrink=0.05),) #i also tried this, and didn't work too.


plt.plot(x,h(x), label="grafica 1")  
plt.plot(x,g(x), label="grafica 2")


plt.legend(loc=1)

annot_max(x,h(x))
annot_max(x,(g(x))

plt.show() 

Without the def annot_max function this is the graphic it shows:

TIM ROBERTS GOT IT RIGHT, IT WAS JUST A TYPO. THANKS TIM