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View Full Version : Pre cal verify


boergoat
Feb 18, 2008, 05:39 PM
sec^4x - 3sec^2x - 4 = 0

galactus
Feb 18, 2008, 06:09 PM
A way to go about a problem like this is to let u=sec^{2}(x)

Then you get a quadratic you can solve:

u^{2}-3u-4=0