C-09-Q135mediumsingle_mcqcos45∘=?\cos 45^\circ = ?cos45∘=?a12\dfrac{1}{2}21b12\dfrac{1}{\sqrt{2}}21c32\dfrac{\sqrt{3}}{2}23d111ব্যাখ্যাWith OM=aOM = aOM=a as the adjacent side and hypotenuse OP=a2OP = a\sqrt{2}OP=a2, .