The answer in itself is 1/128 and here is the procedure to prove it:
cos(A)*cos(60+A)*cos(60-A) = cos(A)*(cos²60 - sin²A)
<span>= cos(A)*{(1/4) - 1 + cos²A} = cos(A)*(cos²A - 3/4) </span>
<span>= (1/4){4cos^3(A) - 3cos(A)} = (1/4)*cos(3A) </span>
Now we group applying what we see above
<span>cos(12)*cos(48)*cos(72) = </span>
<span>=cos(12)*cos(60-12)*cos(60+12) = (1/4)cos(36) </span>
<span>Similarly, cos(24)*cos(36)*cos(84) = (1/4)cos(72) </span>
<span>Now the given expression is: </span>
<span>= (1/4)cos(36)*(1/4)*cos(72)*cos(60) = </span>
<span>= (1/16)*(1/2)*{(√5 + 1)/4}*{(√5 - 1)/4} [cos(60) = 1/2; </span>
<span>cos(36) = (√5 + 1)/4 and cos(72) = cos(90-18) = </span>
<span>= sin(18) = (√5 - 1)/4] </span>
<span>And we seimplify it and it goes: (1/512)*(5-1) = 1/128</span>
Answer:
C. A set of 2 or more
Step-by-step explanation:
Answer:
You still have 30 friends
Step-by-step explanation:
Give me brainliest, I answered first
PUT THIS SET IN ORDER FROM LEAST TO GREATEST:
10, 16, 28, 45, 55, 63, 75, 84
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MEDIAN: Find the number in the middle of the set.
10, 16, 28, 45, 55, 63, 75, 84
There cannot be two medians, so you find the number between 45 & 55.
MEDIAN = 50
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MEAN: Find the average by adding up all of the numbers and dividing them by how many numbers there are.
10 + 16 + 28 + 45 + 55 + 63 + 75 + 84 = 376
376/8 = 47
MEAN = 47
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MODE: The number that occurs most often. If no number repeats, there's no mode.
THERE IS NO MODE
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RANGE: The difference between the largest and smallest value in the set. Subtract the largest (84) and smallest (10) value.
84 - 10 = 74
RANGE = 74
98 x 863 = ?
Answer is 84,574
