I really need help. Create an appropriate table of values for the function f(x)=tan3x/7x and use the re to estimate lim as x approaches 0 tan3x/7x

I'm sure you can make the table.

You know that sinu/u -> 1 as u ->0
since cos(0) = 1, that means that

tanu/u -> 1 as u -> 0

You have

tan3x/7x = tan3x / (3x)*(7/3)
= (tan3x/3x) * 3/7

so, what do you think the limit is?