+1, I was very grateful to MIT OCW because when I learned Linear algebra, I could not have afforded it. Later when I got a job, I donated to OCW and I bought hi

+1, I was very grateful to MIT OCW because when I learned Linear algebra, I could not have afforded it. Later when I got a job, I donated to OCW and I bought his book full price from his own site [1] just as a tribute to the guy. [1] https://math.mit.edu/~gs/linearalgebra/ https://math.mit.edu/~gs/linearalgebra/