Question

SinA= 4/6 SinB=8/9
sin(A+B)=?

Answer 1

Answer:

there is a formula of doing this sum

sin(a+b)=sina.cosb+cosa.sinb

sin a=4/6. cosb=8/9

sin²a +cos²a=1

16/36 +cos²a=1

cos²a=1-16/36

=20/36

cosa=√20/√36

=2√5/6

sin²b+cos²b=1

64/81 +cos²b=1

cos²b=1-64/81

=17/81

cosb=√17/9

now,

sin(a+b)=4/6*8/9+2√5/6*√17/9

=32/54+2√95/4

=34√95/54. is the answer

HOPE THIS HELP