sumy i różnice funkcji trygonometrycznych

Question 1

sin(a)+sin(b)

Answer 1

2sin(a+b / 2)*cos(a-b / 2)

Question 2

sin(a)-sin(b)

Answer 2

2sin(a-b / 2)*cos(a+b / 2)

Question 3

cos(a)+cos(b)

Answer 3

2cos(a+b / 2)*cos(a-b /2)

Question 4

cos(a)-cos(b)

Answer 4

-2sin(a+b / 2)*sin(a-b /2)

Question 5

sin(a)*sin(b)

Answer 5

-(1/2)*(cos(a+b)-cos(a-b))

Question 6

cos(a)*cos(b)

Answer 6

(1/2)*(cos(a+b)+cos(a-b))

Question 7

sin(a)*cos(b)

Answer 7

(1/2)*(sin(a+b)+sin(a-b))