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2 years ago

The roots of the function f(x)=x^2-2x-3 are shown. what’s the missing number

Mathematics

1 answer:

aliya0001 [1]2 years ago

8 0

Answer:

its 6

Step-by-step explanation:

i calculated but threw in trash by an accident

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−p(d+z)=−2z+59. solve for z.

densk [106]

-pd - pz = -2z + 59
-pz = -2z + 59 + pd
-pz + 2z = 59 + pd
-z(p - 2) = 59 + pd
-z = 59 + pd over p - 2
z = -59 + pd/p - 2.

6 0

3 years ago

Read 2 more answers

Show that if X is a geometric random variable with parameter p, then

Lubov Fominskaja [6]

Answer:

$\sum_{k=1}^{\infty} \frac{p(1-p)^{k-1}}{k}=-\frac{p ln p}{1-p}$

Step-by-step explanation:

The geometric distribution represents "the number of failures before you get a success in a series of Bernoulli trials. This discrete probability distribution is represented by the probability density function:"

$P(X=x)=(1-p)^{x-1} p$

Let X the random variable that measures the number os trials until the first success, we know that X follows this distribution:

$X\sim Geo (1-p)$

In order to find the expected value E(1/X) we need to find this sum:

$E(X)=\sum_{k=1}^{\infty} \frac{p(1-p)^{k-1}}{k}$

Lets consider the following series:

$\sum_{k=1}^{\infty} b^{k-1}$

And let's assume that this series is a power series with b a number between (0,1). If we apply integration of this series we have this:

$\int_{0}^b \sum_{k=1}^{\infty} r^{k-1}=\sum_{k=1}^{\infty} \int_{0}^b r^{k-1} dt=\sum_{k=1}^{\infty} \frac{b^k}{k}$ (a)

On the last step we assume that $0\leq r\leq b$ and $\sum_{k=1}^{\infty} r^{k-1}=\frac{1}{1-r}$ , then the integral on the left part of equation (a) would be 1. And we have:

$\int_{0}^b \frac{1}{1-r}dr=-ln(1-b)$

And for the next step we have:

$\sum_{k=1}^{\infty} \frac{b^{k-1}}{k}=\frac{1}{b}\sum_{k=1}^{\infty}\frac{b^k}{k}=-\frac{ln(1-b)}{b}$

And with this we have the requiered proof.

And since $b=1-p$ we have that:

$\sum_{k=1}^{\infty} \frac{p(1-p)^{k-1}}{k}=-\frac{p ln p}{1-p}$

4 0

3 years ago

If 3 times a square of an integer is added to 1 times the integer, the result is 2

jarptica [38.1K]

Let unknown integer be n.

So then your sentence would translate to 3n² + n = 2.

If you need to solve for n then we can move 2 to left side by subtract both sides by 2:

3n² + n - 2 = 0

Now you can factor:

3n² + 3n -2n - 2 = 0

3n( n + 1 ) - 2( n + 1 ) = 0

( 3n - 2 )( n + 1 ) = 0

3n - 2 = 0 OR n + 1 = 0

3n = 2 OR n = -1

n = 2/3 OR n = -1

Final answer: n = 2/3 OR n = -1

6 0

3 years ago

Please help! 50 points

LiRa [457]

Find the oz
divide 243 by 15

5 0

3 years ago

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Is AJKL = AMNO? If so, name the congruence postulate that applies.

romanna [79]

Answer:A that is what I think the answer is

6 0

2 years ago