Cho biểu thức : A=(√x+1)/(√x-2) +(2√x)/(√x+2 )+(2+5√x)/(4-x)
a.Rút gọn A
b.Tính giá trị của A khi x=2
c.Tính giá trị của A khi X-5√x+6=0

Answer:

The correct solution is "(0.092, 0.148)".

Step-by-step explanation:

Given:

Sample size,

n = 500

True proportion,

[tex]\hat {p} = \frac{60}{500}[/tex]

  [tex]=0.12[/tex]

The standard error will be:

[tex]SE=\sqrt{\frac{\hat p(1-\hat p)}{n} }[/tex]

     [tex]=\sqrt{\frac{0.12(1-0.12)}{500} }[/tex]

     [tex]=\frac{0.12(0.88)}{500}[/tex]

The confidence interval is "1.96".

hence,

The required confidence interval will be:

= [tex](\hat p - 1.96 SE, \hat p + 1.96 SE)[/tex]

By substituting the values, we get

= [tex](0.12-1.96\sqrt{\frac{0.12(0.88)}{500} }, 0.12+1.96\sqrt{\frac{0.12(0.88)}{500} } )[/tex]

= [tex](0.092, 0.148)[/tex]

Answer:

26

Step-by-step explanation:

[tex]8^{2} + 20^{2} = 21.5^{2}[/tex]

[tex]21.5^{2} + 14^{2} = 25.7^{2} \\x = 25.7[/tex]

Answer:

c

Step-by-step explanation:

9514 1404 393

Answer:

  D.

Step-by-step explanation:

The wording "when x is an appropriate value" is irrelevant to this question. That phrase should be ignored. (You may want to report this to your teacher.)

When you look at the answer choices, you see that all of them are negative except the last one (D). When you look at the problem fraction, you see that it is positive.

The only reasonable choice is D.

__

Your calculator can check this for you.

  √12/(√3 +3) ≈ 3.4641/(1.7321 +3)

  = 3.4641/4.7321 ≈ 0.7321 = -1 +√3

__

If you want to "rationalize the denominator", then multiply numerator and denominator by the conjugate of the denominator. The conjugate is formed by switching the sign between terms.

  [tex]\displaystyle\frac{\sqrt{12}}{\sqrt{3}+3}=\frac{\sqrt{12}}{(\sqrt{3}+3)}\cdot\frac{(\sqrt{3}-3)}{(\sqrt{3}-3)}=\frac{\sqrt{36}-3\sqrt{12}}{3-9}\\\\=\frac{6-3\cdot2\sqrt{3}}{-6}=\boxed{-1+\sqrt{3}}[/tex]

_____

Additional comment

We "rationalize the denominator" in this way to take advantage of the relation ...

  (a -b)(a +b) = a² -b²

Using this gets rid of the irrational root in the denominator, hence "rationalizes" the denominator.

We could also have multiplied by (3 -√3)/(3 -√3). This would have made the denominator positive, instead of negative. However, I chose to use (√3 -3) so you could see that all we did was change the sign from (√3 +3).

Answer:

Answer is b

Step-by-step explanation:

cuh cuh cuh cuh cuh cuh , , , , , ,,

Answer:

Let the two equal angles be x . Hence the third angle is 3x . But the sum of the interior angles of a triangle always adds up to 180∘ . ∴x=1805=36∘

Answer:

Angle 1 = 36°

Angle 2 = 36°

Angle 3 = 108°

Step-by-step explanation:

Sum of all angles in any triangle is 180°

angle 1 = angle 2 = X

angle 3 = 3×X

angle 1 + angle 2 + angle 3 = 180°

X + X + 3×X = 5×X = 180°

X = 180° / 5 = 36°

Angle 1 = 36°

Angle 2 = 36°

Angle 3 = 108°

Answer:

5/2

Step-by-step explanation:

The square root of 5 divided by the negative square root of 5 equals -1. 7/2 - 1 = 5/2.

Answer:

a = 3 [tex]\frac{1}{3}[/tex]

Step-by-step explanation:

Given

a + 5 [tex]\frac{2}{3}[/tex] = 9 ← change mixed number to improper fraction

a + [tex]\frac{17}{3}[/tex] = 9 ( multiply through by 3 to clear the fraction )

3a + 17 = 27 ( subtract 17 from both sides )

3a = 10 ( divide both sides by 3 )

a = [tex]\frac{10}{3}[/tex] = 3 [tex]\frac{1}{3}[/tex]

Answer:

We have that the sum of two numbers  is 9

this can be written as:

x + y  = 9

where x is the larger number.

Now we want to write:

"the difference between one more than the larger number and twice the smaller number"

First, remember that the difference between A and B is:

A - B

Then "the difference between one more than the larger number and twice the smaller number"

is:

"one more than the larger number" = ( x + 1)

"twice the smaller number" = 2*y

the difference between these is:

(x + 1) - 2*y

Now we can simplify:

We know that:

x + y = 9

then:

y = 9 - x

replacing that in the equation:

(x + 1) - 2*y

we would get:

x + 1 - 2*(9 - x)

x + 1  -18 + 2x

(x + 2x) + (1 - 18)

3x - 17

This means that we can write:

"the difference between one more than the larger number and twice the smaller number"

as: 3x - 17

[tex]\boxed{\sf tan\theta=\dfrac{p}{b}}[/tex]

[tex]\\ \sf\longmapsto tan\theta=\dfrac{13}{20}[/tex]

[tex]\\ \sf\longmapsto tan\theta=0.6[/tex]

[tex]\\ \sf\longmapsto tan\theta\approx\dfrac{1}{\sqrt{3}}[/tex]

[tex]\\ \sf\longmapsto tan\theta\approx tan60[/tex]

[tex]\\ \sf\longmapsto \theta\approx 60°[/tex]

Given height and surface-area-to-volume ratio: r = 2 * h / (h * SA:V - 2) , Given volume and lateral area: r = 2 * V / A_l , Given base area: r = √(A_b / (2 * π)) , Given lateral area and total area: r = √((A - A_l) / (2 * π)) .

Answer:

-19>t

Step-by-step explanation:

-6>t-(-13)

-6>t +(13)

Subtract 13 from each side

-6-13 > t+13-13

-19>t

Let the ages be 3x and 4x

ATQ

[tex]\\ \Large\sf\longmapsto 4x-3x=5[/tex]

[tex]\\ \Large\sf\longmapsto x=5[/tex]

Now

[tex]\\ \Large\sf\longmapsto Age\:of\:Minu=3x=3(5)=15years[/tex]

[tex]\\ \Large\sf\longmapsto Age\:of\:Sudhir=4x=4(5)=20years[/tex]

Their present ages are 15 and 20 years.

Let the age of Minu be represented by x

Since the difference between their ages is 5 years, then the age of her brother will be x + 5.

Based on the information given in the question, the equation to use in solving the question will be:

x/(x + 5) = 3/4

Cross multiply

(4 × x) = 3(x + 5)

4x = 3x + 15

Collect like terms

4x - 3x = 15

x = 15

Minu's age is 15 years

Therefore, her brother's age will be:

= x + 5

= 15 + 5

= 20 years

In conclusion, their present ages are 15 and 20 years.

Read more on:

https://brainly.com/question/17671517

Answer:

Step-by-step explanation:

A=2  ,B=4  ,C=?

[tex]C^{2}[/tex]=[tex]A^{2}[/tex]+[tex]B^{2}[/tex]

[tex]C^{2}[/tex]=[tex]2^{2}[/tex]+[tex]4^{2}[/tex]

[tex]C^{2}[/tex]=4+16

[tex]C^{2}[/tex]=20

C=[tex]\sqrt{20}[/tex]

Answer:

Step-by-step explanation:

I think you mean 35 seconds because if it was 36 then the answer would be too long so assuming it is 35 seconds the answer is 1 minute or 60 seconds

Answer:

i don't know sorry

Answer:

a

Step-by-step explanation:

-5 shifts the y-intercept down, and it needs to be outside of the modulus as if its in the modulus, the graph would shift 5 units to the right instead

Answer:

A' (8,16)

B' (8,-4)

C' (-16,4)

Answered by GAUTHMATH

Answer:

No, because they are parallel.

Step-by-step explanation:

The lines [tex]p[/tex] and [tex]m[/tex] will not intersect, so Kevin is not correct.

It is given that planes A and B intersects. The plane A contains the line p, m and n on its plane. The lines p and m are parallel to each other. They are identical and move in the same direction.

Since the line p and m are parallel, they will not meet each other at any point because parallel lines does not intersect or meet at a point, they run parallelly along each other.

So, line p and m will not intersect.

Thus the answer is " No, because they are parallel."

Answer:

Step-by-step explanation:

no, because they are parrallel.

Answer:

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Answer:

Step-by-step explanation:

Answer:

Slope is (1/4)

Step-by-step explanation:

The slope is calculated by (6-5)/(5-1)=1/4

Answer:

HOPE IT HELP YOU....

if it is right plz comment me .

Answer:

3.398

Step-by-step explanation:

log(10) 2500 = log(10) (5^2*10^2) = log(10) 5^2 + log(10) 10^2 = 2*log(10) 5 + 2=3.398

Answer:

here I'm confused that whether the selling price is Rs.9,200 or Rs.9.200

any ways you can take the help of below procedure

Step-by-step explanation:

here,

let marked price be X

discount(d)=20%

VAT=15%

SP with VAT= 9200

now,

SP without VAT= SP - VAT of SP

= 9200-15/100 ×9200

= 9200- 1380

=Rs. 1380

again,

SP= MP - D of MP

or,7820= x- 20/100 × x

or, 7820× 100 = 100x- 20x

or,782000=80x

or, 782000/80=X

or, X= 9775.

hence MP is Rs 9775

Answer:  [tex]\$202[/tex]

Step-by-step explanation:

Given

Jennifer has $400 more than Brian

Suppose Brian has x amount initially

So, Jennifer has 400+x

If Jennifer gives 20% of her to Brian, then brian would have two-third of the amount Jennifer left with

[tex]\Rightarrow \dfrac{2}{3}\times [400+x](1-0.2)=[400+x](0.2)+x\\\\\Rightarrow \dfrac{2}{3}\times 0.8\times (400+x)=80+0.2x+x\\\\\Rightarrow 213.334+0.533x=80+1.2x\\\Rightarrow 133.334=0.66x\\\Rightarrow x=\$202.02[/tex]

Thus, Brain has [tex]\$202[/tex]

Given:

The sum of the cubic powers of three rational numbers is -1009.

The ratio between the first number and the second number is [tex]\dfrac{2}{3}[/tex].

The ratio between the first number and the third number is [tex]\dfrac{4}{9}[/tex].

To find:

The three numbers.

Solution:

Let [tex]x,y,z[/tex] be the three numbers, then

[tex]x^3+y^3+z^3=-1009[/tex]                ...(i)

[tex]\dfrac{x}{y}=\dfrac{2}{3}[/tex]

[tex]3x=2y[/tex]

[tex]\dfrac{3}{2}x=y[/tex]                        ...(ii)

[tex]\dfrac{x}{z}=\dfrac{4}{9}[/tex]

[tex]9x=4z[/tex]

[tex]\dfrac{9}{4}x=z[/tex]                         ...(iii)

Using (i), (ii) and (iii), we get

[tex]x^3+\left(\dfrac{3}{2}x\right)^3+\left(\dfrac{9}{4}x\right)^3=-1009[/tex]

[tex]x^3+\dfrac{27}{8}x^3+\dfrac{729}{64}x^3=-1009[/tex]

[tex]\dfrac{64+216+729}{64}x^3=-1009[/tex]

[tex]\dfrac{1009}{64}x^3=-1009[/tex]

[tex]x^3=\dfrac{-1009\times 64}{1009}[/tex]

On simplification, we get

[tex]x^3=-64[/tex]

[tex]x^3=-4^3[/tex]

[tex]x=-4[/tex]

Substituting [tex]x=-4[/tex] in (ii), we get

[tex]\dfrac{3}{2}(-4)=y[/tex]

[tex]-6=y[/tex]

Substituting [tex]x=-4[/tex] in (iii), we get

[tex]\dfrac{9}{4}(-4)=z[/tex]

[tex]-9=z[/tex]

Therefore, the three numbers are -4, -6 and -9 respectively.

Answer: $265

Step-by-step explanation: I just added all the numbers together.

Answer:

B. 64:25

Step-by-step explanation:

the ratio of the surface areas =

(8)² : (5)² = 64 : 25