May 9, 2013 Thread starter #1 N Niall New member Apr 24, 2013 1 The tangent P(3,9) on the curve y = x^2, cuts the x-axis at T and PN is perpendicular to the x-axis. Find the length of TN. So far I have: dy/dx = 2x dy/dx = 6 y - 9 = 6(x - 3) y = 6x - 9 Making point T (3/2, 0), but how do you find point N? Thank you.

The tangent P(3,9) on the curve y = x^2, cuts the x-axis at T and PN is perpendicular to the x-axis. Find the length of TN. So far I have: dy/dx = 2x dy/dx = 6 y - 9 = 6(x - 3) y = 6x - 9 Making point T (3/2, 0), but how do you find point N? Thank you.

May 9, 2013 #2 ZaidAlyafey Well-known member MHB Math Helper Jan 17, 2013 1,667 We have got that PN is perpendicular to the x-axis what do we conclude ?