Ask question

Ask question

All categories

3 years ago

11

Resuelve estas ecuaciones

1 answer:

Natali [406]3 years ago

4 0

E. 5x^2 - 10= 0; 5(x^2 - 2)= 0; x^2= 2; x = √2

f. x^2 - x=0; x(x -1)= 0; x = 0, x= 1

g. 4x^2 + 4x= 0 ; 4x( x + 1) = 0; x = 0, x = -1

h. -x^2 + x = 0; -x(x - 1)= 0; x = 0, x = 1

You might be interested in

The International Air Transport Association surveys business travelers to develop quality ratings for transatlantic gateway airp

motikmotik

Answer:

The 95% confidence interval for the population mean rating is (5.73, 6.95).

Step-by-step explanation:

We start by calculating the mean and standard deviation of the sample:

$M=\dfrac{1}{n}\sum_{i=1}^n\,x_i\\\\\\M=\dfrac{1}{50}(6+4+6+. . .+6)\\\\\\M=\dfrac{317}{50}\\\\\\M=6.34\\\\\\s=\sqrt{\dfrac{1}{n-1}\sum_{i=1}^n\,(x_i-M)^2}\\\\\\s=\sqrt{\dfrac{1}{49}((6-6.34)^2+(4-6.34)^2+(6-6.34)^2+. . . +(6-6.34)^2)}\\\\\\s=\sqrt{\dfrac{229.22}{49}}\\\\\\s=\sqrt{4.68}=2.16\\\\\\$

We have to calculate a 95% confidence interval for the mean.

The population standard deviation is not known, so we have to estimate it from the sample standard deviation and use a t-students distribution to calculate the critical value.

The sample mean is M=6.34.

The sample size is N=50.

When σ is not known, s divided by the square root of N is used as an estimate of σM:

$s_M=\dfrac{s}{\sqrt{N}}=\dfrac{2.16}{\sqrt{50}}=\dfrac{2.16}{7.071}=0.305$

The degrees of freedom for this sample size are:

$df=n-1=50-1=49$

The t-value for a 95% confidence interval and 49 degrees of freedom is t=2.01.

The margin of error (MOE) can be calculated as:

$MOE=t\cdot s_M=2.01 \cdot 0.305=0.61$

Then, the lower and upper bounds of the confidence interval are:

$LL=M-t \cdot s_M = 6.34-0.61=5.73\\\\UL=M+t \cdot s_M = 6.34+0.61=6.95$

The 95% confidence interval for the mean is (5.73, 6.95).

4 0

4 years ago

What is y+7/3=y/3 i really need help fast

Y_Kistochka [10]

Y should equal -7/2 or -3.5

3 0

3 years ago

Two trains leave stations 480 miles apart at the same time and travel toward each other. One train travels at 110 miles per hour

kicyunya [14]

Answer:hold on

Step-by-step explanation:

ill hekp

4 0

3 years ago

An apple orchard has an average yield of 40 bushels of apples per tree if tree density is 28 trees per acre. For each unit incre

Mandarinka [93]

Answer:

24 trees per acre

Step-by-step explanation:

Let x be the optimal tree density per acre and y be the number of bushels yield per tree

Since for each unit change of x from 28 trees/acre, we have 2 unit change of y from 40 bushels per tree in the reversed direction

Change of x from 28 is x - 28

Change of y from 40 is y - 40

Therefore we have y - 40 = -2(x - 28) or y = 40 - 2(x - 28) = -2x + 96

The total bushels per acre should be y bushels/tree * x tree/acre. We want to optimize this. Substitute the above equation in for y and we have

$T = xy = x(-2x+96)$

$T = -2x^2 + 96x$

To find the maximum value of this, we can take the first derivative and set it to 0

$T^{'} = -4x + 96 = 0$

$4x = 96$

$x = 24$

We know this is a maxima because $T{''} = -4 < 0$ . So T is maximum when x = 24 trees per acre

7 0

4 years ago

Which choice should i pick<br> A.0.27<br><br> B.0.25<br><br> C.0.07<br><br> D.0.33

Vladimir79 [104]

Answer:

B.0.25

Step-by-step explanation:

7 0

3 years ago