The function y=2cosleft(frac3x4right)y = 2\\cos\\left(\\frac{3x}{4}\\right)y=2cosleft(frac3x4right) has a period TTT. What is the period?
2pi2\\pi2pi
frac8pi3\\frac{8\\pi}{3}frac8pi3
frac2pi3\\frac{2\\pi}{3}frac2pi3
frac6pi4\\frac{6\\pi}{4}frac6pi4