Array ( [0] => Array ( [title] => L28A [link] => https://www.youtube.com/embed/4gf-L_hFYnA ) [1] => Array ( [title] => L28B [link] => https://www.youtube.com/embed/lwKNnLC5Tkk ) [2] => Array ( [title] => L28C [link] => https://www.youtube.com/embed/Cs-bv6xjmkc ) [3] => Array ( [title] => L28D [link] => https://www.youtube.com/embed/LzL455ZFWyg ) ) 國立清華大學開放式課程OpenCourseWare(NTHU, OCW) - 第28R講 10.2 Orthogonal families of functions