Question

Find an equation of the tangent line to: y=1/Sqrt[x]
at x=9 ?

Answer 1

Slope, tangent, derivative. ;o

Answer 2

\[y=\frac{1}{\sqrt{x}}\]\[y=x^{-1/2}\]\[\frac{dy}{dx}=-\frac{1}{2}x^{-3/2}\]

Answer 3

Find the derivative of the function first, and then substitute the value of x to find the slope of the tangent line.

To form an equation of a line you need a slope and a point--you know the x-value fr the point, all you need is the y. ^^ Then boom,

y=m(x-p)+q and you have your equation