5. 1000
6. 100
7. 10
8. 0.9
9. 0.1
I think those are it. I am unsure
Answer:
See below.
Step-by-step explanation:
1. (1 / 2)[cos(a – b) – cos(a + b)]
= 1/2 ( cosa cosb + sina sinb - (cosa cosb - sina sinb)
= 1/2 ( cosa cosb - cosa cos b + sina sinb + sina sinb)
= 1/2 ( 2 sina sinb)
= sina sinb.
(I used the 2 identities cos(a - b) = cosa cosb + sina sinb) and
cos (a + b) = cosa cosb - sina sinb.)
2. sin (π/2 - x) = sin (π/2) cos x - cos(π/2) sin x
= 1 * cos x - 0 * sinx
= cosx - 0
= cos x.
(I used the identity sin(a - b) = sina cosb - cosa sinb
and the fact that sin(π/2) = 1 and cos (π/2) = 0. )
Lets say we have 7 items, and we add 7 more.
Then, in the next situation, we have 7 items and we add 8 more. Now we know that 8 = 7 + 1, so we are actually performing 7 + 7 +1. Our diagram already shows us the value of 7 + 7 so we just add 1.
The items can be represented by circles, triangles etc
Answer:
5.9, 47/8, and 
Step-by-step explanation:
I did this before, Please Mark brainliest
You either need to add the two times together or you need to subtract them