Hi there!

We are given:
cos(7x)cos(4x) = -1 - sin(7x)sin(4x)
Begin by moving all terms with variables to one side:
cos(7x)cos(4x) + sin(7x)sin(4x) = -1
The corresponding trig identity is cos(A - B). Thus:
cos(7x - 4x) = cos(7x)cos(4x) + sin(7x)sin(4x) = -1
cos(3x) = -1
cos = -1 at π, so:
3x = π
x = π/3
We can also find another solution. Let 3π = -1:
3x = 3π
x = π
Thus, solutions on [0, 2π) are π/3 and π.
Answer:
C. chemical energy is what it's stored in the form of
Answer:
21.8° (22° to the nearest degree)
Step-by-step explanation:
Using cosine law:
a² = b² + c² - 2bc(cosA)
3² = 5² + 7² - 2(5)(7)cosA
cosA = 13/14
A = 21.7867893
Approximately angle: 22°
Answer: you could make a chart using guess and check
The set of scores has a mean of 5 and a standard deviation of 2. The score which corresponds to a z score of -2.0 is 1.
Given in the question,
Mean (m) = 5
Standard deviation σ =2
Z-score = -2
The score x,
= Z = x - m / σ
= -2 = x - 5 / 2
= -4 = x - 5
= x = 1
Standard deviation in statistics means the amount of dispersion or variations in the set of values. A lower standard deviation means the value is closer to the mean while a higher standard deviation means the value is farther away from the mean.
To learn more about standard deviation, mean, median, and mode,
brainly.com/question/27878918
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