1. ## horizontal tangent line

determine the points if any at which the gragh of the finction has a horizontal line.
Can any one help explain this.
y= x^4 - 2x^2+3

2. Originally Posted by Nightasylum
determine the points if any at which the gragh of the finction has a horizontal line.
Can any one help explain this.
y= x^4 - 2x^2+3
find the derivative of the function y ...

$y' = 4x^3 - 4x$

set the derivative equal to 0 and solve for x