Answer:
cos(a + b) = 
Step-by-step explanation:
cos(a + b) = cos(a).cos(b) - sin(a).sin(b) [Identity]
cos(a) = 
cos(b) = 
Since, terminal side of angle 'a' lies in quadrant 3, sine of angle 'a' will be negative.
sin(a) = 
[Since, sin(a) = 
]
= 
= 
Similarly, terminal side of angle 'b' lies in quadrant 2, sine of angle 'b' will be negative.
sin(b) = 
= 
= 
By substituting these values in the identity,
cos(a + b) = 
= 
= 
=
Therefore, cos(a + b) =
Answer:
Step-by-step explanation:
To solve this, we can imagine a line drawn directly down from the point (10,4) to the x-axis. This would make a right triangle with length 10 and height 4.
is equal to the length of adjacent leg to the angle divided by the length of the hypotenuse of the triangle. From the picture, we can see the adjacent leg is 10.
We can use Pythagorean's Theorem to find the hypotenuse (let 
represent the length of the hypotenuse):
Thus, we know the adjacent is 10, and the hypotenuse is 
. This means .
Hope this helps!
Answer:
HMmMm I think the answer is yes
Which one is the red ties that were drawed?
25 * 10 = 250
20 * 10 = 200
55 * 10 = 550
Above: Which ever one is the red one, that's what I think is the answer. Hopefully that helped! :)
