1. Find the derivative of f[x,}r,z) = x312 in the direction of the velocitv vector ofthe helix t] = {cos(t) , sinit) , t) at t = E. 2. Let x, ya} = x2}? + xv'l + 2. Find the derivative offat {1,2,3} in the direction of II = 2i +j 2k. 3. Find the equation of the tangent plane to the surface 2 = 1% when in: = v = 4, then find the : coordinate where the tangent plane intersects the zaxis. 4. Find the equation of the tangent plane to the surface 1:2 + 3:2 + 22 2x3: + 4x: x + y = 11 at the point {2,3,1}. 2 5. Find the linearization off(x,}r) = x2 x}? + y? + 3 at the point {3,2}. 6. Find the number of critical points that the function f{x,y} = erxsmy has if [i :1 y E 23:. T. Find and classify.r all critical points for the function f{x,}r) = ZFXE 3:3 18x3! + T. 3. Let f[x,y] = x3 +y3 + 3x2 33:2 3. Find the local minimum and local maximum