One algebra question i cannot get?

Question

ive got all but this one done,

#22. a - 1 / a + 1 + a + 1 / a - 1

Answer 1

- 1 / a + 1 + a + 1 / a - 1

common denom : a-1*a+1

-1* ( a-1) + (a+1)(a-1)

--------------

a-1*a+1

but we knwo a-1*a+1 = a^2 -1

-a+1 + a^2 -1

-------------------

a^2 -1

a^2 -a

-----------

a^2 -1

a(a-1)

---------

(a+1)(a-1)

a

-----

a+1

Answer 2

Hi,

a - 1....a + 1

------.+.-------- =

a +1....a - 1

Multiply the first fraction on top and bottom by (a - 1) and multiply the second fraction on top and bottom by (a + 1) to get a common denominator. Then simplify the numerators and combine.

(a-1)²...... ....(a+1)²

--------------.+.-------------- =

(a+1)(a-1)....(a-1)(a+1)

(a-1)².....(a+1)²

--------.+.---------- =

a² - 1.....a² - 1

a²-2a+1....a²+2a+1

-----------.+.------------ =

a² - 1..... ....a² - 1

a²-2a+1.+.a²+2a+1

--------------------------- =

..... ....a² - 1

2a² + 2

----------- <==ANSWER if I understood your original problem

a² - 1

I hope that helps!! :-)

Answer 3

idk

Answer 4

2a+2

Answer 5

a+1+a+1=

2a+2