Show all the steps to get full credit. 1. (12 points) Find the limit of each function if it exists; or show that the limit does not exist. x-y+1 (a) lim (x,y)-(4,3) x-y-1 Irm (1x-4) (fx + 4+) (814)-> (43) (x-7-1) (8x+(y+1) 4xy2 (b) lim (x,y)-(0,0) x+y+ 4 X (y + 1) 2 (x-x-1) (Bx+ (x4) 4-(3+1) (4-3-1) (1319) lim 4642 along the x-axis: 4zO 420 (x,y)- (0,0) x+44 2 Irm DNE (x,y)- (0,0) x+44 (x,y) - (0,0) 4 2 (rm (x, y)-7 (0,0)+2 along the y-axis: x = 5/2 2 510 DNG O 21 DNE 2. (12 points) Find the indicated partial derivative of each function. Do not simplify af (a) Find of the function f(x,y) = exylny-sin x+y 2 f(x, y) = exy (ny - son Fx+1/1/2 2 2x = ex - 1 son (x+4) Jy = (b) Find of the function f(x,y) = tan-1,x = ucosv, y = usinv Iv y' Joey) = fun = Fan -1 x fx = tan Y Y Jy = fan-1 another different path 2