Recall the sum identity for cosine:
cos(a + b) = cos(a) cos(b) - sin(a) sin(b)
so that
cos(a + b) = 12/13 cos(a) - 8/17 sin(b)
Since both a and b terminate in the first quadrant, we know that both cos(a) and sin(b) are positive. Then using the Pythagorean identity,
cos²(a) + sin²(a) = 1 ⇒ cos(a) = √(1 - sin²(a)) = 15/17
cos²(b) + sin²(b) = 1 ⇒ sin(b) = √(1 - cos²(b)) = 5/13
Then
cos(a + b) = 12/13 • 15/17 - 8/17 • 5/13 = 140/221
Answer:50
Step-by-step explanation:
All you do is add 60 and 70 together and then subtract what you had got from 180 witch gives you the answer for y and sense x is vertical to y they are going to be the same.
Answer:
The answer is 234
Step-by-step explanation:
Answer:
452.4 cm
Step-by-step explanation:
the formula for the area of a circle is A = pi r^2
Answer:
w>-5/12
Step-by-step explanation:
w > 1/3 - 3/4 = 4/ 12 - 9/ 12
w> -5/12
