Question

(Algebra) Find the sum of x+a; if {x;a} c Q+

Answer 1

\[x^{x}=(2^{x})^{-1}\] and \[a^{2}=27^{a-1}\]

Answer 2

i think if \(x^x=2^{-x}\) then \(x=\frac{1}{2}\)

Answer 3

great now I can not find a.

Answer 4

that because \(2^{-x}=(\frac{1}{2})^x\)

Answer 5

yeah that kind of sucks
maybe we can guess

Answer 6

i guess 1

Answer 7

it is a good guess, because it obviously works
unfortunately, it is not the only correct answer

Answer 8

I've got the answer but I do not know how to find a. I mean the process.

Answer 9

try a= 1/3
I need to know how T_T

Answer 10

as we say in the math biz, find \(a\) "by inspection"

Answer 11

you cannot solve this with algebra, so forget that
you can perhaps solve by graphing both and see where they intersect

Answer 12

but in the exam is not allowed to use calculator or a computer

Answer 13

ok then you just have to guess

Answer 14

apparently there are three answers

Answer 15

i am guessing you are looking for some step by step algorithm for solving this, but i am fairly certain there is not one
you have to guess and check

Answer 16

you've got a point

Answer 17

there is a negative answer also, but i don't know what it is, probably not rational

Answer 18

in my book there's only one. I'd like to have a algebra teacher to help me out. Do you have a teacher? Can you ask them?

Answer 19

try it in wolfram, when you get the answer, go to "approximate form' you will see that the negative answer is probably not a repeating decimal

Answer 20

Please Forgive me English is not my first language

Answer 21

clearly there is more than one answer
there are three, although if the negative answer in not rational you can ignore that one

Answer 22

your english seems pretty good to me

Answer 23

maybe the book just ignored the obvious answer of 1 and used only \(\frac{1}{3}\)

Answer 24

ok thanks. I'm trying to solve another one. Would you like to see it?

Answer 25

sure

Answer 26

\[(\sqrt{\sqrt{2+\sqrt{3}}+\sqrt{2-\sqrt{3}}}+ \sqrt[4]{6})^{4}\] and the answer in the book and calculator is 96.

Answer 27

but we do not use calculator in the classroom, I do, but at home