Question

if a,b are acute acute angles,tan a=5/12, then cos(a+b)​

Answer 1

Step-by-step explanation:

ANSWER

REF.Image

∴sinA=4/5,cosA=3/5

sinB=5/13,cosB=12/13

∴sin(A+B)=sinAcosB+cosAsinB

=

5

4

.

13

12

+

5

3

.

13

5

=

65

48+15

=

65

63

=(D)

Answer 2

Answer:

16/65 :-))))))))))))))))