Answer:
hence cos ( 2 A ) = cos 2 A − ( 1 − cos 2 A ) = 2 cos 2 A − 1
Step-by-step explanation:Well we know that for two angles A , B
it holds that cos ( A + B ) = cos A cos B − sin A ⋅ sin B hence for A = B you get cos ( 2 A ) = cos 2 A − sin 2 A But sin 2 A = 1 − cos 2 A
Answer:
dhdhrjfidgegehfr fhfn fhc fn dncc c. f byn
(a + 1)(a² + 2a + 1)
= a(a² + 2a + 1) + 1(a² + 2a + 1)
= a³ + 2a² + a + a² + 2a + 1
= a³ + 3a² + 3a + 1
Answer: b
Answer:
a) Suppose that F is ordered in ascending order: 
. Then, the complement of F can be written as
which is the union of a finite number of open intervals, then 
is an open set. Thus, F is a closed subset of the real numbers.
b) Take an arbitrary element of F, let us say 
. Now, choose a real number 
such that
there are not other element of F, because is less that the minimum distance between and its neighbors.
In case that 
we only consider 
, and if 
we only consider 
.
Then, all points of F are isolated.
Step-by-step explanation:
Answer: 3/8ths
Step-by-step explanation: 1/8+1/8+1/8=3/8
