What is the gradient of the function u = ln (x + y + Z) at point m (1,2, - 2)

RELATED INFORMATIONS

• 1. Let y = y (x) be the implicit function determined by the functional equation E ^ (x + y) = 2 + X + 2Y at points (1, - 1), and find y "| (1, - 1) and Let y = y (x) be the implicit function determined by the functional equation E ^ (x + y) = 2 + X + 2Y at points (1, - 1), and find the quadratic differential of Y "| (1, - 1) and dy
• 2. The first and second partial derivatives of XYZ = x + y + Z I want to know more about it
• 3. Let z = f (XY, x ^ 2-y ^ 2), where f has the second order continuous partial derivative, find a ^ Z / ax ^ 2
• 4. If y = (x, z) is obtained from z = f (x, y), then does the partial derivative (AZ / ay) (ay / AZ) = 1 hold
• 5. Let z = f (x squared - y squared, XY), calculate AZ / ax, AZ / ay
• 6. Let X / z = ln (Z / y), find AZ / ax, AZ / ay
• 7. If the function z = ln (x + Y / 2x), then the partial derivative AZ / ay=
• 8. Let y = ln (XY) find the partial derivative ᦉ 8706; Z / ᦉ 8706; X
• 9. Let z = f (x ^ 2 + y ^ 2, XY), where f has a continuous partial derivative of the first order, and then find ᦉ 8706; Z / ᦉ 8706; X
• 10. Let f (x) be defined in (- ∞, + ∞), f (0) not equal to 0, f (XY) = f (x) f (y). It is proved that f (x) = 1
• 11. Let f (x) and G (x), H (x) = max {f (x), G (x)}, u (x) = min {f (x), G (x)}. How to express H (x), u (x) with F (x), G (x)? Let f (x) and G (x) be continuous in the same interval, where H (x) = max {f (x), G (x)}, u (x) = min {f (x), G (x)}. How to express H (x), u (x) with F (x), G (x) and some operational symbols such as "+", "-"?
• 12. Define f (x) = max [f (x), G (x)], known function f (x) = x ^ 2-x-3, G (x) = x + 5, find the maximum value of F (x) Define f (x) = max [f (x), G (x)], that is, when f (x) ≥ g (x), f (x) = f (x); when f (x) < g (x), f (x) = g (x). Given the function f (x) = x ^ 2-x-3, G (x) = x + 5, find the maximum value of F (x) It's a hard fight. Can anyone solve it? ??? why is it the maximum, not the minimum
• 13. Let the function f (x) be defined on the number set X. it is proved that the necessary and sufficient condition for the function f (x) to be bounded on X is that it has both upper and lower bounds on X Thank you very much for the concrete proof process given by the great God~
• 14. Define Max {a, B} = {B, AB}, then the range of F (x) = max {2 ^ x, 2 ^ - x} is?
• 15. What does it mean to have a definition in a function of higher numbers?
• 16. Let u = f (x, z) and Z (x, y) be a function determined by the equation z = x YP (z)
• 17. Z = e (x-2y) x = Sint y is equal to the square of t to find DZ / DT
• 18. Let z = e ^ (x-2y), and x = Sint, y = T ^ 3, find DZ / dt
• 19. Let the function z = f (x, y) be determined by the equation XY + YZ + XZ = 1, and find ᦉ 8706; 2Z / ᦉ 8706; (x ^ 2)
• 20. The problem of partial derivative of higher number Z = (1 + XY) ^ y, how to find the partial derivative of Y?