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PDF] A Chebyshev-based rectangular-polar integral solver for scattering by geometries described by non-overlapping patches | Semantic Scholar
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calculus - Evaluate integral limits using the antiderivatives expression, with a calculator - Stack Overflow
![Could someone help me solve this? I tried an integral calculator online but it gave me a solution with something called sec. I don't know what sec is, I haven't learned about Could someone help me solve this? I tried an integral calculator online but it gave me a solution with something called sec. I don't know what sec is, I haven't learned about](https://preview.redd.it/could-someone-help-me-solve-this-i-tried-an-integral-v0-xspizs23kp3a1.png?width=640&crop=smart&auto=webp&s=ab22e400ad624e7c8e66a91a7bebe335cea243b0)