Question

Please help! Click on attached PLEASE

Answer 1

sin a sin b = (1/2) [ cos (a-b) - cos (a + b)]

Answer 2

i'd better make sure thats correct

Answer 3

http://www.sosmath.com/trig/prodform/prodform.html
this link contains them

Answer 4

yes thats the one

so if you plug in a=45 and b = 15 you'll see the correct choice

Answer 5

Oh, I see. I worked through it and I think it's the third choice. Am I right?

Answer 6

no
there are 2 cos's in the answer

Answer 7

(1/2 ) [cos(45-15) - cos (15+45)]

Answer 8

its either 2nd or 4th

Answer 9

The only difference is the -. I'm thinking the second.

Answer 10

? How do I know for sure

Answer 11

:/

Answer 12

its the 4th
they've put the negative first

Answer 13

1/2 [ cos 30 - cos 60]

= 1/2 [-c0s 60 + cos 30]

Answer 14

ok?

Answer 15

Ok, I get it. Thanks!

Answer 16

yw