jessbri806 jessbri806 13-12-2022 Mathematics contestada Find the equation for the plane tangent to each surface z = f(x, y) at the indicated point. (a) z = x3 + y3 − 5xy, at the point (1, 2, 1) (b) z = (cos(x))(cos(y)), at the point (0,π/2,0) (c) z = (cos(x))(sin(y)), at the point (0,π/2,1)