Question

find the value of

Answer 1

what are the answers they give you to choose from? @msingh

Answer 2

there are no answers given

Answer 3

Ok well I tried my best to type it into my calculator and I got .9993910357
I don't know if that is the right answer or not. You could try to google it.

Answer 4

okay

Answer 5

@amistre64

Answer 6

im thinking some trig identity might help: cos(a+b) = cos(a)cos(b)-sin(a)sin(b)

Answer 7

okay

Answer 8

cos^2(a)cos^2(b)+sin^2(a)sin^2(b) - 2k
cos^2(a)cos^2(b)+sin^2(a)sin^2(b)+ 2k

\[2cos^2(60)cos^2(b)+2sin^2(60)sin^2(b)+cos^2(b)\]

\[cos^2(b)(1+2cos^2(60))+2sin^2(60)sin^2(b)\]
\[cos^2(b)(1+2/4)+6/4~sin^2(b)\]
\[cos^2(b)(6/4)+6/4~sin^2(b)=3/2\]

Answer 9

@amistre64
thank u

Answer 10

yw

Answer 11

but @amistre64
i getting the answer
after solving, that is
cos^2 theta(3/2)

Answer 12

i got it down to:

\[\frac64(cos^2(\theta)+sin^2(\theta))\]
\[\frac64(1)\]

Answer 13

how u got
2sin^2(60)sin^2(b) part

Answer 14

this part will be gonna cancel

Answer 15

i took and squared out the cos(a+-b) parts

Answer 16

cos(a+b) = cos(a)cos(b)-sin(a)sin(b)
cos(a-b) = cos(a)cos(b)+sin(a)sin(b)

square those and you end up with

2cos^2(a)cos^2(b)+2sin^2(a)sin^2(b)

Answer 17

okay

Answer 18

with that in hand, and an extra cos^2(b) to factor with

itll simplify