I've been working on this problem for awhile now but I think it's easier than I'm making it seem. Here's what I have so far:

3sec^2x = 4

sec^2x = 4/3

secx = sqrt 4/3

It seems right to me but of course sqrt 4/3 isn't a proper answer, since it's not within the domain of sec x. Am I doing this right, and is the answer 'undefined,' or is there something wrong? Please help me, thanks.