Question

Find the gradient of t = x^2y+ e^z at the point p(1,5,-2)

(a) i + 10j + 0.135k

(b) 10i + j + 0.135k

(c) i + 0.135j + 10k

(d) 10i + 0.135j + k

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Question is taken from Gradient in section Vector Calculus of Electromagnetic Theory

Answer 1

Right answer is (b) 10i + j + 0.135k

The best explanation: Grad(t) = 2xy i + x^2 j + e^z k. On substituting p(1,5,-2), we get 10i + j + 0.135k.