Step-by-step explanation:
cos(A + B) cos(A − B)
Use angle sum/difference formulas:
(cos A cos B − sin A sin B) (cos A cos B + sin A sin B)
Distribute:
cos² A cos² B − sin² A sin² B
Use Pythagorean identity:
cos² A (1 − sin² B) − (1 − cos² A) sin² B
Distribute:
cos² A − sin² B cos² A − (sin² B − sin² B cos² A)
cos² A − sin² B cos² A − sin² B + sin² B cos² A
cos² A − sin² B
Answer:
functions cant have the same x vaule
im not sure which is a "set" since all the numbers are all under the same line
(3,4) (4,5) (5,6) (6,7) would be function
(1,6) (1,7) (3,4) (2,8) wouldnt be a function because of the 1
Q. how many factors does 15 have?
1, 3, 5, 15 so 15 has 4 factors
Step-by-step explanation:
