In the adjoining figure, the line segment PQ is parallel to side AC of triangle ABC and it divides the triangle into two parts having equal area, then the ratio \(\frac{AP}{AB}\) equals :
1
\(\frac{1}{\sqrt{2}}\)
2
\(\frac{\sqrt{2}}{1}\)
3
\(\frac{1}{\sqrt{3}}\)
4
\(\frac{2−\sqrt{2}}{2}\)