C-09-Q106mediumsingle_mcqIf cosA+sinA=2cosA\cos A + \sin A = \sqrt{2}\cos AcosA+sinA=2cosA, then cosA−sinA=?\cos A - \sin A = ?cosA−sinA=?a2sinA\sqrt{2}\sin A2sinAb2cosব্যাখ্যাSquaring or rearranging, from cosA+sinA=2cosA\cos A+\sin A=\sqrt{2}\cos AcosA+sinA=2cos we get . Then .