[tracker[0].getVelocity is not a function]

I remplaced getVelocity("x") by get("x") can you say me if this two methods is looklike 

[tracker[0].getVelocity is not a function]

@mikel Thanks for your response but i'm Greensock club membership and inertial plugin is in my package (greensock club) and i have download Inertia plugin file

[tracker[0].getVelocity is not a function]

Hello All,

I use inertiaPlugin but when i want to use getVelocity() methods this dont work !! 

 

can you help me,  maybe in GSAP 3 getVelovity() not exist ? 

my error is :  tracker[0].getVelocity is not a function 

tracker is :

 

1. VelocityTracker {target: div.c-exp-gallery__inner.js-experience-slider__inner, _props: {…}}
   1. target: div.c-exp-gallery__inner.js-experience-slider__inner
   2. _props: {x: u}
   3. __proto__: Object