Q. If r=∣r∣, where r=x^+y^+zk^, then prove that \vec{\(\newline\)abla} .*** END OF PAPER ***
Identify vector and magnitude: Identify the vector r and its magnitude r.r=xi^+yj^+zk^r=x2+y2+z2
Calculate gradient of r: Calculate the gradient of r. \(\newlineabla(r) = abla(\sqrt{x^2 + y^2 + z^2})\) Using the chain rule, \(\newlineabla(r) = \frac{1}{2}(2x, 2y, 2z) / \sqrt{x^2 + y^2 + z^2}\) = (rx,ry,rz)
Recognize unit vector: Recognize that (rx,ry,rz) is the unit vector of r. Since r=x2+y2+z2, dividing each component by r normalizes the vector. Thus, (rx,ry,rz)=rr
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