The Cordic Algorithm, Theory and FPGA Uses

There's a bit of history cobbled together with no explanation of why that's important. There's some equations with only half the terms defined - in particular, what is i? The equations are screenshots from a basic word processing application - the cursor is visible in some of them. There's a mention of gain and how to calculate it, but no explanation of what it is or why it's relevant to anything. There are two paragraphs on convergence, with a subheading 'Convergence' between those two paragraphs, but no explanation of what's converging or what it's converging to.

There's a run-through with no commentary on how to implement this on an FPGA using one tool, and a screenshot of the output with no explanation of what's relevant or whether it's the expected output.

At the very bottom, there's a line reading 'Sponsored by AMD'. If I were the person at AMD who signed off on this, I'd be asking for my money back.