You can clone with
HTTPS or Subversion.
After dividing by cos squared, the next line switches the order of the terms on the left side of the equation. That can confuse some users. Tan squared should be first, not 1.
The line after "Plugging into our expression, we get" should be an equation, so the user understands we just went back to the original problem statement.
["<code style=\"display: none;\">1</code>"]
Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:16.0) Gecko/20100101 Firefox/16.0
MathJax is loaded, ready, queue length: 0
User hash: 1954125845
Solved issue #32130.
Submitted pull request: #32141