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. )
Your answer is Graph A :)
Answer:
11
Step-by-step explanation:
d=√(5-(-6))²+(-7-(-7))²
d=√(11²+0²)
d=11
Answer:
Top right answer
Step-by-step explanation:
He added the -x to 4x when he should have subtracted.
Answer:
62.5
Step-by-step explanation:
1. convert percent value to decimal
30.00/100=.3
2. turn problem into equation where x equals the original price
x*.3=18.75
3. solve
(x*.3=18.750)/.3
x=62.5