Answer:
cosA + sinA
Step-by-step explanation:
Using trig. identities :
cos(A + B) = cosAcosB - sinAsinB
cos2A = cos²A - sin²A
cos2A = (cosA + sinA)(cosA - sinA)
Therefore, your question is :
=> cos2A/(cosA - sinA)
=> (cosA + sinA)(cosA - sinA)/(cosA - sinA)
=> cosA + sinA
