Question

(where does the 1/2 come from in this)
Simplify cos(a+pi/3)
cos a cos π/3 - sin a sin π/3
cos a [ 1/2 ] - (√3/2) sin a
(1/2) [ cos a - √3 sin a ]

Answer 1

The 1/2 come from the fact that:
\[\cos(\pi/3)=1/2\]

Answer 2

And\[\sin(\pi/3)=\sqrt{3}/2\]

Answer 3

@John_ES in the last step where does the two go from sqtrt3/2?

Answer 4

oh wait nvm i typed it out wrong that's why it was gone lol

Answer 5

@muddahamburglar are you still having issues with this question?

Answer 6

yes i am @freckles

Answer 7

can you tell me which part?

Answer 8

notice in
(1/2) [ cos a - √3 sin a ]

the ½ is "outside" the brackets which act as parens.

if you distribute the ½ you will get back
½ cos a - sqr(3)/2 sin a

you can "factor out" the ½ and go back to
(1/2) [ cos a - √3 sin a ]

Answer 9

@freckles actually i think i get now thank you so much though!

Answer 10

k