We expand first (cos x +cos y)^2+(sin x-sin y)^2:
= cos^2 x + 2 cos x cos y + cos^2 y+ sin ^2 x + sin ^2 y - 2 sin x sin y
= (cos^2 x + sin ^2 x) + (cos^2 y + sin ^2 y) + 2 (cos x cos y - sin x sin y)
then, apply the trigonometric identities of addition and summation of angles
= 1 + 1 + 2 cos (x+y)
we add the following identities above that results to
2 + 2 cos (x+y)
Answer:
am not sure but
Step-by-step explanation:
since they are similar they must have similar ratio
so 12/4 =3/1
so 3:1
4*3=12
for other sides I think
9*3 =27
and
6*3=18
y=27
x=18
Answer:
Step-by-step explanation:
A do-decagon is a polygon with 12 straight sides and 12 equal angles.
-The general formula for finding area of a do-decagon is given as:
where s is the sides length.
-Given the sides dimension is 9cm, the area is calculated as;
Hence, the do-decagon's area is
He uses 1/5 OF 5/6 of a yard. That "of" is very important, because it indicates that, to find the answer, you multiply the two together.
That being said (1/5) times (5/6) =5/30, which can be reduced to 1/6 yds to make the frame
Answer: A sequence of numbers that has an ending rather than no ending.
There are infinite sequences and finite sequences in mathematics.