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Question: Find the cross product a × b and


Find the cross product a × b and verify that it is orthogonal to both a and b.
a = t i + cos t j + sin tk, b = i - sin t j + cos tk


> Show that the curvature is related to the tangent and normal vectors by the equation dT KN ds

> Find the vectors T, N, and B, at the given point. r(t) = (r?.3r", t), (1.7, 1)

> Use the formula in Exercise 42 to find the curvature. Formula in Exercise 42: x = et cos t, y = et sin t |ty – yx|| K = [t? + y? ]/2

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> Use Theorem 10 to show that the curvature of a plane parametric curve x = f (t), y = g (f) is where the dots indicate derivatives with respect to t. |ty – yx|| K = [t? + y? ]/2

> Use a graphing calculator or computer to graph both the curve and its curvature function k (x) on the same screen. Is the graph of  what you would expect? y = x-2

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> If u(t) = r(t) ∙ [r'(t) × r''(t)], show that u'(t) – r(t) ∙ [r'(t) × r'''(t)]

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> Sketch the curve with the given vector equation. Indicate with an arrow the direction in which t increases. r(t) = cos t i - cos t j + sin t k

> Use Formula 11 to find the curvature. y = x4

> Prove Formula 6 of Theorem 3.

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> Evaluate the integral. t 1 k) dt 1 - t j+ V1 – 12

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> Use Theorem 10 to find the curvature. r(t) = t i + t2 j + et k

> Use Theorem 10 to find the curvature. r(t) = t3 j + t2 k

> (a). Find the unit tangent and unit normal vectors T(t) and N(t). (b). Use Formula 9 to find the curvature. r(t) = (r, }r°, r²)

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2.99

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