3 (5) Let a1 az = az = b 5 (a) (10 points) Determine whether b is in Span{a1, a2, a3}. If yes, write b as a linear combination of a1, a2, a3; if not, explain why not. (b) (10 points) Let T : R R be a linear transformation such that T = a1, T( |1) = a2, T = a3. Determine whether there is a vector x R such that T(x) = b. Justify your answer.