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1 vote
What is the difference?

2x + 5/x 2 - 3x - 3x + 5/x3 - 9x - x + 1/x2 - 9


(x + 5)(x + 2)/x3 - 9x

(x + 5)(x + 4)/x3 - 9x

-2x + 11/x3 - 12x - 9

3(x + 2)/x2 - 3x


Edit: It's A

What is the difference? 2x + 5/x 2 - 3x - 3x + 5/x3 - 9x - x + 1/x2 - 9 (x + 5)(x-example-1
User Oren S
by
4.6k points

2 Answers

1 vote

Answer:

A

Explanation:

User English Grad
by
4.2k points
3 votes

Answer:

The option
((x+5)(x+2))/(x^3-9x) is correct

The difference of the given expression is


(2x+5)/(x^2-3x)-((3x+5)/(x^3-9x))-({(x+1)/(x^2-9))=((x+5)(x+2))/(x^3-9x)

Explanation:

Given expression is
(2x+5)/(x^2-3x)-((3x+5)/(x^3-9x))-({(x+1)/(x^2-9))

To find the difference of the given expression as below :


(2x+5)/(x^2-3x)-((3x+5)/(x^3-9x))-({(x+1)/(x^2-9))


=(2x+5)/(x(x-3))-((3x+5)/(x(x^2-9)))-({(x+1)/(x^2-9))


=(2x+5)/(x(x-3))-((3x+5)/(x(x^2-3^2)))-({(x+1)/(x^2-3^2))


=(2x+5)/(x(x-3))-((3x+5)/(x(x-3)(x+3)))-({(x+1)/((x-3)(x+3)))

( using the formula
a^2-b^2=(a+b)(a-b) )


=(2x+5(x+3)-(3x+5)-x(x+1))/(x(x-3)(x+3))


=(2x^2+6x+5x+15-3x-5-x^2-x)/(x(x-3)(x+3)) (adding the like terms)


=(x^2+7x+10)/(x(x^2-9)) ( by factoring the quadratic polynomial )


=((x+5)(x+2))/(x^3-9x)

Therefore
(2x+5)/(x^2-3x)-((3x+5)/(x^3-9x))-({(x+1)/(x^2-9))=((x+5)(x+2))/(x^3-9x)

Therefore the difference of the given expression is


((x+5)(x+2))/(x^3-9x)

Therefore option
((x+5)(x+2))/(x^3-9x) is correct

User Agus
by
4.9k points