sand dollar. n. 1. Any of various thin circular echinoderms of the order Clypeasteroida, especially Echinarachnius parma, of coastal northern Atlantic and Pacific waters, having a covering of short movable spines.
One reason why linear algebra is very useful is that linear transforms of normal variables are normal. If x ~ N(a, A), then Bx+b ~ N(Ba+b, BABT). In a way, when everything is linear and normal, everything is nice and analytically tractable.
Math skills are needed throughout a chemistry course. Algebra is used to solve equations by un-doing whatever is being done to an unknown variable. For example, if an equation has âx+2â then you would subtract â2â to solve for âxâ.