Soru
Q2. Given f(x,y,z)=x^2-y^2+2mx^2 and a point P(2,1,-1) then a. Find forall f(x,y,z) and (r(2.1,-1) b. Find the directional derivative of f(x,y,z) at P(2,1,-1) in the direction of u=langle 1,-1,sqrt (2)rangle
Çözüm
4.7
(291 Oylar)
Senem
Elit · 8 yıl öğretmeni
Uzman doğrulaması
Cevap
To find the gradient of the function \( f(x, y, z) = x^2 - y^2 + 2mx^2 \) at the point \( P(2, 1, -1) \), we need to compute the partial derivatives of
with respect to
,
, and
.The partial derivatives are:
Evaluating these partial derivatives at the point \( P(2, 1, -1) \):
So, the gradient vector at \( P(2, 1, -1) \) is:
Next, we need to find the directional derivative of
at \( P(2, 1, -1) \) in the direction of the unit vector
.First, we normalize the unit vector
:
The directional derivative of
in the direction of
is given by the dot product of the gradient vector and the unit vector
:
So, the directional derivative of
at \( P(2, 1, -1) \) in the direction of
is
.