Question

simplify cos60deg cos30deg-sin60degsin30deg

Answer 1

0

Answer 2

hint \[\cos ( a + b) = \cos a \cos b - \sin a \sin b\]
does that help?

Answer 3

yes but i got another one involving vector if you got a moment

Answer 4

that seems very distant from this topic...

Answer 5

never mind the vector could you give me some more information on simplifying the above expression

Answer 6

if u dont kne that formula ...just subs values of cos 60 and cos 30 and sin

Answer 7

like i told you...use that formula i gave...for example \[\cos(20) \cos (40) - \sin(20)\sin (40) \implies \cos (20 + 40) \implies \cos (60)\]

Answer 8

ok i would like to say thank you and move on to a harder question, sin2A/1+cos2A

Answer 9

I would like to say please start a new post for a new question, thanks!

Answer 10

ok