Find an equation of the tangent line to the graph at the given point. (The graph is called a Witch of Agnesi.)


f(x)= 7 / x^2 + 3

(2,1)

1 answer

the slope is -14x/(x^^2+3)^2, so at (2,1) the slope is -28/49 = -4/7

Now you have a point and a slope, so the line is

y-1 = -4/7 (x-2)

See the graphs at

http://www.wolframalpha.com/input/?i=plot+y%3D7%2F(x%5E2%2B3),+y+%3D+-4%2F7+(x-2)%2B1