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3 years ago

Evaluate the series 9 + 3 + 1 +

Mathematics

1 answer:

ryzh [129]3 years ago

8 0

Answer:

9 + 3 + 1 + ......... = 13.5

Step-by-step explanation:

The series 9 + 3 + 1 + is the sum of an infinite geometric sequence. The first term of the series is 9 while the common ratio is 1/3;

to obtain the common ratio we obtain the quotient of any two successive terms, 3/9 or 1/3.

The sum of an infinite geometric series with first term a and common ratio r is given by;

$S_{n}=\frac{a}{1-r}$

Plug in the values of a and r into the formula;

$S_{n}=\frac{9}{1-\frac{1}{3} }\\\\\\S_{n}=\frac{27}{2}=13.5$

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Can the following question be considered a statistical question and why or why not?

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Yes, it specifies the population

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3 years ago

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3 years ago

Simplify the following

den301095 [7]

Answer:

1) 11 $\sqrt{3}$

2) 2 $\sqrt{2}$

3) $20\sqrt{3} + 15\sqrt{2}$

4) $53 + 12\sqrt{10}$

5) -2

6) $7\sqrt{2} - 5\sqrt{3}$

Step-by-step explanation:

1) 2 $\sqrt{12}$ + 3 $\sqrt{48}$ - $\sqrt{75}$

=(2 × 2 $\sqrt{3}$ )+ (3 × 4 $\sqrt{3}$ ) - 5 $\sqrt{3}$

= 4 $\sqrt{3}$ + 12 $\sqrt{3}$ - 5 $\sqrt{3}$

= 11 $\sqrt{3}$

2) 4 $\sqrt{8}$ -2 $\sqrt{98}$ + $\sqrt{128}$

= (4 × 2 $\sqrt{2}$ ) - (2 × 7 $\sqrt{2}$ ) + 8 $\sqrt{2}$

= 8 $\sqrt{2}$ - 14 $\sqrt{2}$ +8 $\sqrt{2}$

= 2 $\sqrt{2}$

3) 5 $\sqrt{12\\}$ - 3 $\sqrt{18} + 4 \sqrt{72} +2\sqrt{75}$

= 5× $2\sqrt{3}$ - 3× $3\sqrt{2}$ + 4× $6\sqrt{2}$ + 2× $5\sqrt{3}$

= $10\sqrt{3} - 9\sqrt{2} +24\sqrt{2} +10\sqrt{3}$

= $20\sqrt{3} + 15\sqrt{2}$

4) $(2\sqrt{2} + 3\sqrt{5} )^{2}$

= $8 + 12\sqrt{10} + 45$

= $53 + 12\sqrt{10}$

5) $(1+\sqrt{3} ) (1-\sqrt{3} )$

= $1 - 3$

= -2

6) $(2\sqrt{6} -1) (\sqrt{3} -\sqrt{2} )$

= $2\sqrt{18}-2\sqrt{12} -\sqrt{3} +\sqrt{2}$

= 2× $3\sqrt{2}$ - 2× $2\sqrt{3}$ - $\sqrt{3} + \sqrt{2}$

= $6\sqrt{2} - 4\sqrt{3} -\sqrt{3} +\sqrt{2}$

= $7\sqrt{2} - 5\sqrt{3}$

Hope the working out is clear and will help you. :)

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2 years ago

Read 2 more answers

A race car game takes 6 points from a player each time the player hits a cone. What integer represents the change in total point

Helga [31]

Given:

A race car game takes 6 points from a player each time the player hits a cone.

To find:

The integer which represents the change in total points if the player hits 10 cones.

Solution:

According to the given information,

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Here, negative sign represents the reduction in points after hitting a cone.

If the player hits 10 cones.

(1 × 10) hit = (-6 × 10) points

10 hit = -60 points

So, the change in total points if the player hits 10 cones is -60.

Therefore, the required integer is -60.

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3 years ago

For the problem, use the discriminant to determine the number of real solutions for the equation. Then, find the solutions and c

Ksivusya [100]

Answer:

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The solution t1 doesn't make sense for this problem, as we can't have a negative value for the time.

So the solution is t2 = 0.35 s

Step-by-step explanation:

To find the time when the ball will reach the height of 2 meters, we just need to use the value of h = 2 in the equation given. So, we have that:

−4.9t^2 − 4t + 4 = 2

−4.9t^2 − 4t + 2 = 0

For this equation, we have the constants a = -4.9, b = -4 and c = 2. So the discriminant Delta is:

Delta = b^2 - 4ac = 16 + 39.2 = 55.2

sqrt(Delta) = 7.4297

As Delta > 0, we have 2 real solutions

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t2 = (-b - sqrt(Delta)) / 2a = (4 - 7.4297) / (-9.8) = 0.35 s

Number of real solutions: 2

Solutions: t1 = -1.1663 s and t2 = 0.35 s

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So the solution is t2 = 0.35 s

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3 years ago