While substituting values in taylor series, while substituting values for 3x^2, I didn’t get why x was substituted with 3,

because we are calculating ( 27 + .0001 )^3, so x value should be 3 right ?

Not sure if am missing out on something here.

Could someone please clarify ?

Right.

f(x)=x^3 and using Taylor Series it calculates value at f(x+\Delta{x}), where. x=3, and~ \Delta{x}=0.0001

So there is a mistake in the video, the values is getting calculated at (3+0.0001)^3 *not* (27+0.0001)^3