Question

cos. of 23 degrees?

Answer 1

cos(a-b) = cosa cosb + sina sinb
cos(a+b) = cosa cosb - sina sinb

cos23 = cos(60-37)
cos(60-37) = cos60 cos37 + sin60 sin37
= (1/2)(4/5) + (sqrt of 3 /2) (3/5)

Answer 2

\[(4/10) + (3\sqrt{3}) /10 = (1/10) (4+3\sqrt{3})\]

Answer 3

english please? lol ur dealing with a blonde here

Answer 4

that's the formula
you can get \[\cos 23^{o} \]
from \[\cos(60^{o}-37^{o})\]

Answer 5

cos(a-b) = cosa cosb + sina sinb
so for cos23 ->
cos(60-37) = cos60 cos37 + sin60 sin37
we know that cos60 is 1/2
cos 37 is 4/5
sin 60 is \[\sqrt{3}/2\]
and sin 37 is 3/5
then just plug the values of those sin and cosine to the formula

Answer 6

...ok

Answer 7

0.424?