Hi, I'm using the book "Linear Algebra" fourth edition by Stephen H. Friedberg, Arnold J. Insel and Lawrence E. Spence. It's a first level university algebra course (after the college level).
The question is Let T:P2(R)-->R^3 be defined by T(f(x))=(f(-1), f(0), f(1)). Is T invertible? Compute T^(-1) if it exists.
Unfortunately the book and the class notes do far from spoon feed you. I have many other questions but if a few of them are answered maybe I'll figure out how to approach these problems.