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:
A
Step-by-step explanation:
Answer:
ORDER THEM FROM LEAST TO GREATEST THEN CROSS OFF A NUMBER FROM EACH SIDE TILL YOU ARE LEFT WITH ONE IN THE MIDDLE
ANSWER IS 17
Step-by-step explanation:
Answer:
Hello! answer 9/1000
Step-by-step explanation:
All you have to do is multiply the probability of each then you will get your answer so...
6/20 × 4/20 × 3/20 = 9/1000 So thats your probability. Hope that helps!
Answer:
A: (10k+m)(10k−m)
Step-by-step explanation:
