3. (10 pts ea) Find the limit if it exists or show that the limit does not exist. (a) lim xy (x,y)-(0,0) x2+ y2 (b) lim Hint: see example 4. (x, y)->(0,0) x + y 2x2 + 3y2 (c lim (x,y)->(0,0) 2x2+ 3y2+1-1\fShow your work/reasoning. Be neat and orderly. Solve on scratch paper first. Simplify answers