[r] Remove specific rows from a data frame

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removing specific rows from a dataframe

Let's say I have a data frame consisting of a number of rows, like this:

X <- data.frame(Variable1=c(11,14,12,15),Variable2=c(2,3,1,4))

Variable1    Variable2
11           2
14           3
12           1
15           4

Now, let's say that I want to create a new data frame that is a duplicate of this one, only that I'm removing all rows in which Variable1 has a certain numerical value. Let's say we have these numbers stored in a vector, v.

That is, if v contains the numbers 11 and 12, the new data frame should look like this:

Variable1    Variable2
14           3
15           4

I've been searching the net for quite some time now trying to figure out how to do something like this. Mainly, I would just need some kind of command saying removeRow(dataframe, row) or something like that.