I need help, again, again, because people keep trolling. :|

How to solve this? Is the question correct? ty :)

bezimeni [28]

Answer:

The proposition is true.

Step-by-step explanation:

Now we proceed to demostrate that expression given is true by algebraic means:

1) $\frac{x^{-1}+y^{-1}}{x^{-1}}+\frac{x^{-1}-y^{-1} }{y^{-1}}$ Given

2) $\frac{y^{-1}\cdot (x^{-1}+y^{-1})+x^{-1}\cdot (x^{-1}-y^{-1})}{x^{-1}\cdot y^{-1}}$ $\frac{a}{b} + \frac{c}{d} = \frac{a\cdot d+b\cdot c}{b\cdot d}$

3) $\frac{x^{-1}\cdot y^{-1}+y^{-2}+x^{-2}-x^{-1}\cdot y^{-1}}{x^{-1}\cdot y^{-1}}$ Distributive property/ $a^{b}\cdot a^{c} = a^{b+c}$

4) $\frac{x^{-2}+y^{-2}}{(x\cdot y)^{-1}}$ Commutative, associative and modulative properties/Existence of additive inverse/ $a^{b}\cdot c^{b} = (a\cdot c)^{b}$

5) $[(x\cdot y)^{-1}]^{-1}\cdot (x^{-2}+y^{-2})$ Commutative property/Definition of division

6) $(x\cdot y)\cdot (x^{-2}+y^{-2})$ $(x^{-1})^{-1}$

7) $x^{-1}\cdot y + x\cdot y^{-1}$ Distributive property/Associative property/ $a^{b}\cdot a^{c} = a^{b+c}$

8) $(x^{-1}\cdot y^{-1})\cdot y^{2} + (x^{-1}\cdot y^{-1})\cdot x^{2}$ Modulative property/Existence of additive inverse/ $a^{b}\cdot a^{c} = a^{b+c}$

9) $(x^{-1}\cdot y^{-1})\cdot (x^{2}+y^{2})$ Distributive property

10) $(x\cdot y)^{-1}\cdot (x^{2}+y^{2})$ $a^{b}\cdot c^{b} = (a\cdot c)^{b}$

11) $\frac{x^{2}+y^{2}}{x\cdot y}$ Commutative property/Definition of division/Result

4 0

3 years ago

Simplify this expression 3x^2 y^2/24x

maksim [4K]

The answer would be (1/8) (xy ^ 2).
Equation:
3x ^ 2 y ^ 2 / 24x

=(3/24) (x ^ 2 y ^ 2 / x)
SO simplify it is
= (1/8) (xy ^ 2)

The simplified expression for this case is given by:
(1/8) (xy ^ 2)

4 0

3 years ago

Read 2 more answers

Kwan's parents bought a home for $50,000 in 1997 just as real estate values in the area started to rise quickly. Each year, thei

poizon [28]

A. First let us start with the linear model.

The equation is in the form of y = m x + b

Calculating for the slope m:

m = (309,587 – 50,000) / (2007 – 1997)

m = 25,958.7

Subsituting:

y = 25,958.7 x + b

Taking x = 1997, y = 50,000. Solve for b:

50,000 = 25,958.7 (1997) + b

b = -51,789,523.9

The complete equation is therefore:

y = 25,958.7 x - 51,789,523.9

B. The exponential model has the following form:

y = a b^x

where a and b are constants

Taking x1= 1997, y1 = 50,000; x2 = 2007, y2 = 309,587

50,000 = a b^1997

309,587 = a b^2007

Combining in terms of a:

50,000 / b^1997 = 309,587 / b^2007

b^2007 / b^1997 = 309,587 / 50,000

b^10 = 6.19174

b = 1.2

Substituting:

y = a 1.2^x

Solving for a:

50,000 = a 1.2^1997

a = 3.75 x 10^-154

The complete equation is:

y = 3.75 x 10^-154 * 1.2^x

3 0

4 years ago

What must be added to each term of the ratio 2:5 so that it maay be equal to 5:6

Kaylis [27]

9514 1404 393

Answer:

13

Step-by-step explanation:

Let n represent that number.

(2 +n)/(5 +n) = 5/6 . . . . . . . . n is added to numerator and denominator

6(2 +n) = 5(5 +n) . . . . . . . . . multiply by 5(5+n)

12 +6n = 25 +5n . . . . . . . . . eliminate parentheses

n = 13 . . . . . . . . . . . subtract 5n+12

Adding 13 to each term will give 5/6.

__

<em>Check</em>

(2 +13)/(5 +13) = 15/18 = (3·5)/(3·6) = 5/6

_____

<em>Alternate solution</em>

The difference of denominator and numerator in 2/5 is 5-2 = 3. The difference of denominator and numerator in 5/6 is 6-5 = 1. In order to make the latter difference 3, we must have (3/3)(5/6) = 15/18. We can get 15/18 from 2/5 by adding 13 to numerator and denominator.

7 0

3 years ago

The following probability distributions of job satisfaction scores for a sample of information systems (IS) senior executives an

Mashcka [7]

Answer:

Step-by-step explanation:

To calculate ;

1) the expected value of the job satisfaction score for senior executives ;

expected value = Summation (Px)

= 1 x 0.05 + 2 x 0.09 + 3 x 0.03 + 4 x 0.42 + 5 x 0.41

= 4.05

2) the expected value of the job satisfaction score for middle managers;

= 1 x 0.04 + 2 x 0.10 + 3 x 0.12 + 4 x 0.46 + 5 x 0.28

= 3.84

c) the variance of job satisfaction scores for executives and middle managers (to 2 decimals).

Executives ; Variance = Summation(PX^2 - Summation(PX)^2

i) For Executive Managers = 1 x 0.05 + 2^2 x 0.09 + 3^2 x 0.03 + 4^2 x 0.42 + 5^2 x 0.41 - 4.05^2 = 1.246 = 1.25

ii) for middle managers ; 1 x 0.04 + 2^2 x 0.10 + 3^2 x 0.12 + 4^2 x 0.46 + 5^2 x 0.28 - 3.84^2 = 1.134 = 1.13

d) the standard deviation of job satisfaction scores for both probability distributions (to 2 decimals). Executives, Middle managers;

For Executives = square root [ 1 x 0.05 + 2^2 x 0.09 + 3^2 x 0.03 + 4^2 x 0.42 + 5^2 x 0.41 - 4.05^2] = 1.12

For Middle Managers ; Square root [1 x 0.04 + 2^2 x 0.10 + 3^2 x 0.12 + 4^2 x 0.46 + 5^2 x 0.28 - 3.84^2 ] = 1.06

e) from the values gotten for the variance of both executive and middle managers, the variance of the former is more than that of the latter as such higher satisfaction with the executive managers.

5 0

3 years ago