(tan²(<em>θ</em>) cos²(<em>θ</em>) - 1) / (1 + cos(2<em>θ</em>))
Recall that
tan(<em>θ</em>) = sin(<em>θ</em>) / cos(<em>θ</em>)
so cos²(<em>θ</em>) cancels with the cos²(<em>θ</em>) in the tan²(<em>θ</em>) term:
(sin²(<em>θ</em>) - 1) / (1 + cos(2<em>θ</em>))
Recall the double angle identity for cosine,
cos(2<em>θ</em>) = 2 cos²(<em>θ</em>) - 1
so the 1 in the denominator also vanishes:
(sin²(<em>θ</em>) - 1) / (2 cos²(<em>θ</em>))
Recall the Pythagorean identity,
cos²(<em>θ</em>) + sin²(<em>θ</em>) = 1
which means
sin²(<em>θ</em>) - 1 = -cos²(<em>θ</em>):
-cos²(<em>θ</em>) / (2 cos²(<em>θ</em>))
Cancel the cos²(<em>θ</em>) terms to end up with
(tan²(<em>θ</em>) cos²(<em>θ</em>) - 1) / (1 + cos(2<em>θ</em>)) = -1/2
<span>In
2005, the price of a TV was $1599.00.
In 2002, the price of the same type of tv has dropped to $399.00
Let’s Calculate the percent of decrease.
First subtract 1599 dollars with 399 dollars to know how much did the price of
TV decreased.
=> 1 599 – 399 = 1 200 is the amount the decreased on TV’s price
=> 1 200 / 1599 = 0.75
=> 0.75 * 100% = 75%
Thus, the price of TV had been decreased to 25%, 75% of it were decreased</span>
If I understand it correctly then its complementary angle will be 115˚, because 180-65=115.
Answer:
a. what is the perimeter of a square with side length:
3 cm=12cm
7 cm=28
b.90
Answer:
5.08
Step-by-step explanation:
5 8/100
Since there are 2 zero's in 100, we need two numbers in the top
Replace 8 with 08 which is the same number
5 08/100
Now write as a decimal
5.08
