Find the derivative of the function at p, in the direction of a. f(x, y,z) = 2 e* cos (yz), p. (0,0,0). a = 3i + 3j + 5k dat (type an exact answer, using radicals as needed.)

In the following diagram it is given that dec, ab || dc, ad || eb, and ad is congruent to bc. a)why isn't abc a parallelogram even though it has a pair of parallel sides and a pair of congruent sides b)explain why be must be congruent to bc. further explain what type of triangle this makes triangle abc and what it tells you about angle 1 and angle 2c) finally why must angle 3 be congruent to angle 1? further, explain why we know that angle 3 is congruent to angle 2