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The directional derivative of ϕ = xy + yz + zx along the tangent to the curve at x = t, y = t2, z = t3 at P(1,1,1) is A/√14, then the value of A is:
    Correct answer is '12'. Can you explain this answer?
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    The directional derivative of = xy + yz + zx along the tangent to the ...
    To find the directional derivative of the function f(x,y,z) = xy + yz + zx, we need to find the gradient vector of f at the point P(1,1,1) and then take the dot product of the gradient vector with the tangent vector of the curve at P.

    First, let's find the gradient vector of f:

    ∇f = (∂f/∂x, ∂f/∂y, ∂f/∂z)
    = (y+z, x+z, x+y)

    Now, let's find the tangent vector of the curve at P(1,1,1). We can do this by taking the derivative of each component of the curve with respect to t:

    r(t) = (x(t), y(t), z(t))
    = (t, t^2, t^3)

    dr/dt = (dx/dt, dy/dt, dz/dt)
    = (1, 2t, 3t^2)

    At P(1,1,1), t = 1, so the tangent vector at P is:

    dr/dt = (1, 2(1), 3(1)^2)
    = (1, 2, 3)

    Finally, we can find the directional derivative by taking the dot product of the gradient vector and the tangent vector:

    Directional derivative = ∇f · dr/dt
    = (y+z, x+z, x+y) · (1, 2, 3)
    = (1+1, 1+1, 1+2)
    = (2, 2, 3)

    Therefore, the directional derivative of f = xy + yz + zx along the tangent to the curve at P(1,1,1) is (2, 2, 3).
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    The directional derivative of = xy + yz + zx along the tangent to the ...
    Concept:
    The directional derivative is given by:
    D.D. = grad(ϕ). 
    Calculation:
    grad(ϕ) at P(1,1,1) is:
    The equation of the curve is represented by r(t).
    The tangent of this curve is given by:
    The value of tangent at (1,1,1) is:
    D.D. = 12√14
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    The directional derivative of = xy + yz + zx along the tangent to the curve at x = t, y = t2, z = t3at P(1,1,1) isA/√14, then the value of A is:Correct answer is '12'. Can you explain this answer?
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    The directional derivative of = xy + yz + zx along the tangent to the curve at x = t, y = t2, z = t3at P(1,1,1) isA/√14, then the value of A is:Correct answer is '12'. Can you explain this answer? for Civil Engineering (CE) 2024 is part of Civil Engineering (CE) preparation. The Question and answers have been prepared according to the Civil Engineering (CE) exam syllabus. Information about The directional derivative of = xy + yz + zx along the tangent to the curve at x = t, y = t2, z = t3at P(1,1,1) isA/√14, then the value of A is:Correct answer is '12'. Can you explain this answer? covers all topics & solutions for Civil Engineering (CE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The directional derivative of = xy + yz + zx along the tangent to the curve at x = t, y = t2, z = t3at P(1,1,1) isA/√14, then the value of A is:Correct answer is '12'. Can you explain this answer?.
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