Review the proof of sin(A – B) = sinAcosB – cosAsinB sin(A – B) =

Step 1: Equals cosine left-bracket (StartFraction pi Over 2 EndFraction minus A) + B right-bracket

Step 2: Equals cosine left-bracket StartFraction pi Over 2 EndFraction minus (A minus B) right-bracket

Step 3: Equals cosine (StartFraction pi Over 2 EndFraction minus A) cosine B minus sine (StartFraction pi Over 2 EndFraction minus A) sine B

Step 4: = sinAcosB – cosAsinB

How must the proof be rearranged for the steps to logically follow each other?

a. Step 3 should be step 1.
b. Step 4 should be step 1.
c. Steps 1 and 2 must be switched.
d. Steps 1 and 3 must be switched.