Question

If sin A = 12/13 and sin B = 4/5
then the value of cos (A+B) is?( Trigonometry)​

Answer 1

Answer:

-33/65

Step-by-step explanation:

cos(A+B)=cosAcosB-sinAsinB

sinA=12/13, cosA=$\sqrt{1-sin^{2} A }$= 5/13

cosB= 3/5

cos(A+B)=5/13*3/5 - 12/13*4/5=3/13-48/65= -33/65