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3 years ago

PLEASE HELP ANSWER THESE QUESTIONS!

Mathematics

1 answer:

Sliva [168]3 years ago

7 0

Answer:

Step-by-step explanation:

a² - b² = (a+ b)(a - b)

1) (2n-4/2n) ÷ (n^2-4/n)

$=\frac{2n-4}{2n}*\frac{n}{n^{2}-4}\\\\=\frac{2n-2*2}{2n}*\frac{n}{n^{2}-2^{2}}\\\\=\frac{2*(n-2)}{2n}*\frac{n}{(n+2)*(n-2)}\\\\=\frac{1}{n+2}$

2) [y^2-36/y^2-49] ÷[ y+6/y-7]

$=\frac{y^{2}-36}{y^{2}-49}*\frac{y-7}{y+6}\\\\=\frac{y^{2}-6^{2}}{y^{2}-7^{2}}*\frac{y-7}{y+6}\\\\=\frac{(y+6)*(y-6)}{(y+7)*(y-7)}*\frac{y-7}{y+6}\\\\=\frac{y-6}{y+7}\\$

3) [m^2-1/ m^2-m] ÷ [m^2-7m-8/3m ]

$=\frac{m^{2}-1}{m^{2}-m}*\frac{3m}{m^{2}-7m-8}\\\\=\frac{(m+1)*(m-1)}{m*(m-1)}*\frac{3m}{(m-8)*(m+1)}\\\\=\frac{3}{m-8}$

Hint : m² - 7m - 8

sum = -7

Product = -8

Factor = (-8), 1

m² - 7m - 8 =m² - 8m + m - 8

= m*(m - 8) + (m-8)

= (m - 8)(m +1)

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<h2>Solving the Question</h2>

We're given:

<em>h</em> = 28 million years
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For most questions like this, we would have to plug these values into the equation mentioned above. However, this question asks for the time elapsed after 3 half-lives.

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<h2>Answer</h2>

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A gun mass of 5 kg fired a bullet of mass 10 g with the velocity of 360 km/h. What

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3 years ago

nekit [7.7K]

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Step-by-step explanation:

The first step is to find the ratio of the lengths.

According to the information given in the exercise, one the solids has edges of 12 feet and the other solid has edges of 24 feet.

Therefore, the ratio of the length of the smaller solid to the length of the is the following:

$k=\frac{24\ ft}{12\ ft}\\\\k=2$

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Then, knowing that the volume of the smaller solid is:

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You get that the volime of the larger solid is:

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