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enyata [817]
3 years ago
14

The Greek mathematician Eratosthenes (ca. 276-195 BC) measured the circumference of the earthfrom the following observations. He

noticed that on a certain day the sun shone directly down a deep wellin Syene (modern Aswan). At the same time in Alexandrea, 500 miles north (on the same meridian), therays of the sun shone at an angle of 7.2° to the zenith. Use this information to find theradius and circumference of the earth.

Mathematics
1 answer:
denpristay [2]3 years ago
5 0

Answer:

Radius of the Earth is 3978.8 Miles

Circumference of the Earth is 25000 Miles

Step-by-step explanation:

The angle of the sun shone at an angle of 7.2° to the zenith

This means that the angle of the sector of the circle is 7.2° (θ)

S = Length of the sector of the circle = 500 miles

r = radius of earth

Converting 7.2° to radians

\theta =7.2\frac{\pi}{180}

S=r\theta\\\Rightarrow r=\frac{S}{\theta}\\\Rightarrow r=\frac{500}{7.2\frac{\pi}{180}}\\\Rightarrow r=3978.8\ Miles

∴ Radius of the Earth is 3978.8 Miles

C=2\pi r\\\Rightarrow C=2\times \pi \frac{500}{7.2\frac{\pi}{180}}\\\Rightarrow C=25000\ Miles

∴ Circumference of the Earth is 25000 Miles

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Answer:

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General Formulas and Concepts:

<u>Pre-Algebra</u>

  • Equality Properties

<u>Algebra I</u>

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Step-by-step explanation:

<u>Step 1: Define</u>

f(x) = x² - 14x + 63

<u>Step 2: Rewrite</u>

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We have that
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Answer:

Step-by-step explanation:

Given that,

f(3) = 2

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The linear approximation of "f" at "a" is one way of writing the equation of the tangent line at "a".

At x = a, y = f(a) and the slope of the tangent line is f'(a).

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f(2.85) = 2 + 5(2.85 - 3)

f(2.85) = 2 + 5×-0.15

f(2.85) = 2 - 0.75

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