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3 years ago

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A group of 13 friends were planning a trip. On the night before they left they made a lot of phone calls. Each friend talked to

every friend at least once. What is the fewest phone calls that would have been made.

1 answer:

gavmur [86]3 years ago

6 0

I believe 156 because each person would have had to make 12 phone calls and there are 13 people so 12x13

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Let f(x) = log(x). Find values of a such that f(kaa) = kf(a).

meriva

Answer:

a = $k^{\frac{1}{k-2}}$

Step-by-step explanation:

Given:

f(x) = log(x)

and,

f(kaa) = kf(a)

now applying the given function, we get

⇒ log(kaa) = k × log(a)

or

⇒ log(ka²) = k × log(a)

Now, we know the property of the log function that

log(AB) = log(A) + log(B)

and,

log(Aᵇ) = b × log(A)

Thus,

⇒ log(k) + log(a²) = k × log(a) (using log(AB) = log(A) + log(B) )

or

⇒ log(k) + 2log(a) = k × log(a) (using log(Aᵇ) = b × log(A) )

or

⇒ k × log(a) - 2log(a) = log(k)

or

⇒ log(a) × (k - 2) = log(k)

or

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or

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taking anti-log both sides

⇒ a = $k^{\frac{1}{k-2}}$

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3 years ago

Find the coordinates of point P that lies along the directed line segment AB in a 2:3 ratio given A (-2, 1), B (3, 4).

saul85 [17]

Answer:

$P(x,y) = (0,\frac{11}{5})$

Step-by-step explanation:

Given

$A = (-2,1)$

$B = (3,4)$

$m:n = 2:3$

Required

Determine the coordinates of P

The coordinate of a point when divided into ratio is:

$P(x,y) = (\frac{mx_2 + nx_1}{m + n},\frac{my_2 + ny_1}{m + n})$

Where

$(x_1,y_1) = (-2,1)$

$(x_2,y_2) = (3,4)$

$m:n = 2:3$

This gives:

$P(x,y) = (\frac{2 * 3 + 3 * -2}{2 + 3},\frac{2 * 4 + 3 * 1}{2 + 3})$

$P(x,y) = (\frac{6 - 6}{5},\frac{8 + 3}{5})$

$P(x,y) = (\frac{0}{5},\frac{11}{5})$

$P(x,y) = (0,\frac{11}{5})$

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3 years ago

Function Operations Picture attached

sergeinik [125]

Answer: Second option

Step-by-step explanation:

You need to make the multiplication of the function $c(x)=\frac{5}{x-2}$ and the function $d(x)=x+3$ . Then:

$(cd)(x)=(\frac{5}{x-2})(x+3)$

You need to apply the Distributive property:

$(cd)(x)=\frac{5(x+3)}{x-2}\\\\(cd)(x)=\frac{5x+15}{x-2}$

Therefore, the domain will be all the number that make the denominator equal to zero.

Then, make the denominator equal to zero and solve for x:

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Therefore, the domain is: All real values of x except $x=2$

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3 years ago

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Troyanec [42]

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3 years ago

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Naya [18.7K]

<h2>The number of small buses used = 5</h2><h2>The number of big buses used = 4</h2>

Step-by-step explanation:

Let us assume the total number of small buses needed = x

The capacity of 1 small bus = 40

So, the capacity of x buses = 40(x) = 40 x

Let us assume the total number of big buses needed = y

The capacity of 1 big bus = 50

So, the capacity of y buses = 50(y) = 50 y

Also, the total students travelling = 400

So, the number of students traveling by (Small bus + Big bus) = 400

⇒ 40 x + 50 y = 400 ..... (1)

Also, the total number of drivers available = 9

⇒ x + y = 9 ..... (2)

Also, x ≤ 8, y ≤ 10

Now, solving both equations, we get:

40 x + 50 y = 400 ..... (1)

x + y = 9 ⇒ y = (9-x) put in (1)

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or, 40 x + 450 - 50 x = 400

or, - 10 x =- 50

or, x = 5 ⇒ y = (9-x) = 9- 5 = 4

Hence the number of small buses used = 5

The number of big buses used = 4

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