<p>whats the integral of tan^(2)</p>
<p>Make it sin^2/cos^2. Then turn sin^2 into 1-cos^2 so you have 1-cos^2/cos^2. Then separate the denominator to make it sec^2 - 1. Final answer is tanx - x + C.</p>
<p>Or..wow. I just realized you can use the pythagorean identity to shorten that process greatly. tan^2 + 1 = sec^2.
Thus, than^2 = sec^2 - 1. => tanx - x + C</p>
<p>Yup. Your second one is the way to do it.</p>