In Google Sheets, the function T.DIST(x, degrees_freedom, cumulative) is used to calculate the probability of the Student's t-distribution.

It returns the probability that a value in a Student's t-distribution is less than or equal to x.

The parameters of the T.DIST function are as follows:

x: This is the value at which you want to evaluate the distribution.

degrees_freedom: This represents the degrees of freedom of the distribution. It is the number of observations minus one.

cumulative: This is a logical value that determines the form of the function. If cumulative is set to TRUE, T.DIST returns the cumulative probability.

If cumulative is set to FALSE, T.DIST returns the probability density function (PDF) at the given value of x.

Here's an example of how to use the T.DIST function in Google Sheets:

=T.DIST(2, 10, TRUE)

In this example, we are calculating the cumulative probability of the value 2 in a Student's t-distribution with 10 degrees of freedom.

Note that in more recent versions of Google Sheets, the T.DIST function has been replaced by the T.DIST.2T function, which calculates the two-tailed probability of the Student's t-distribution.

However, T.DIST is still available for backward compatibility.