Answer: see proof below
<u>Step-by-step explanation:</u>
Use the Sum & Difference Identity: cos (A + B) = cos A · cos B - sin A · sin B
Recall the following from Unit Circle: cos (π/2) = 0, sin (π/2) = 1
cos (π) = -1, sin (π) = 0
Use the Quotient Identity: 
<u>Proof LHS → RHS:</u>
Quotient: tan x
LHS = RHS 
Answer:
yea
Step-by-step explanation:
You mean, what is this number?
we can rephrase it like this: the sum of a number x and 8 is 15
which is:
x+8=15
we subtract 8 from both sides and we get
x=7
so the answer is 7.
Hi i need more informacion :)01927. i tgink is octagon
212
/ \
2 106
/ \
2 53
2800
/ \
2 1400
/ \
2 700
/ \
2 350
/ \
2 175
/ \
5 35
/ \
5 7
/ \
7 1
900
/ \
2 450
/ \
2 225
/ \
3 75
/ \
3 25
/ \
5 5
/ \
5 1
This might help if you need it again
