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moongazerBest ResponseYou've already chosen the best response.1
how do you find it? stepbystep please :)
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
√(x^2  9x +20)/√(x^2  5x + 6) I already know the domain. But, how do you get it?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
first workout contraints for squareroot : the thing inside squareroot cannot be negative
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
next work out constraints for denominator : denominator cannot be equal to 0
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
consider numerator first : \(\sqrt{x^2  9x +20}\)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
can u work out domain for that ?
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
{xx>=5} is that right?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
somewhat right :) lets see how to solve
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
x^29x+20 >= 0 x^24x5x+20 >=0 x(x4) 5(x4) >= 0 (x4)(x5) >= 0 x <= 4 or x >= 5
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
thats one constraint for numerator, lets find out the constraints for denominator
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
I think I am starting to understand it :)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
good :) since, denominator is also under radical, it must be >=0 : x^2  5x + 6 >= 0 x^23x2x + 6 >= 0 x(x3) 2(x3) >= 0 (x2)(x3) >= 0 x <= 2 or x >= 3
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
with those two things, we finished with the first step of finding constraints for radicals
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
so far we have this : x <= 4 or x >= 5 x <= 2 or x >= 3
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
yup, I understand it :)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
next one is denominator can never equal to 0. so, x^2  5x + 6 \(\ne\) 0 x^23x2x + 6 \(\ne\) 0 x(x3) 2(x3) \(\ne\) 0 (x2)(x3) \(\ne\) 0 x \(\ne\) 2 or x \(\ne\) 3
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
w8 Isn't it that it should be: x >= 4 or x >= 5 x >= 2 or x >= 3 ???
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
lets combine all constraints and make a meaningful constraint
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
(x4)(x5) >= 0 (x2)(x3) >= 0
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
oh i got ur question, il give quick explanation
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
you comfortable with parabola graph ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
il show u in graph why its x <=4 , x >=5
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
I know few things about parabola
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
im sketching this parabola : (x4)(x5) >= 0
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
it intersect x axis at 4, 5 right ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
dw:1348496600444:dw
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
between 4 and 5, it is sinking down into x axis eh ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
its becoming NEGATIVE
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
dw:1348496705657:dw
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
why did it intersect in x axis at 4, 5?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
when u factored you got : (x4)(x5)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
that means it intersects xaxis at 4 and 5
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
ohh, ok what if it says (x4)(x+5) does it intersect at 4 and 5 ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
thats right, when it says, (x4)(x+5) = 0 then it intersects at 4 and 5
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
cuz for it to equal to 0, one of both of the factors must equal to 0
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
dw:1348498226449:dw
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
so the graph is like that?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
perfect, thats (x4)(x+5)
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
and the domain is x>=4,x<=5 is it correct?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
thats right ! you became expert ;p
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
Thanks! I know understand it. :) let's now continue with our previous discussion :)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
great ! so far what we have
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
next one is denominator can never equal to 0. so, x^2  5x + 6 ≠ 0 x^23x2x + 6 ≠ 0 x(x3) 2(x3) ≠ 0 (x2)(x3) ≠ 0 x ≠ 2 or x ≠ 3
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
lets put down all the 3 constraints we got in one place :
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
1) numerator radical : x <= 4 or x >= 5 2) denominator radical : x <= 2 or x >= 3 3) denominator cant be 0 : x ≠ 2 or x ≠ 3
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
I understand it. What's next?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
can we combine them as one, like this : 2) 3) : x < 2 or x > 3
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
I'll be back just continue.
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
someone is calling me
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
ok after combining 2) and 3) we are left with : 1) numerator radical : x <= 4 or x >= 5 2) x < 2 or x > 3 this is the last step. see if u can figure out
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
out of x < 2 & x <= 4, x < 2 is more restrictive, so we have this in our domain : \(\color{green}{x < 2}\)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
out of x > 3 & x <= 4 x > 3 , x <= 4 , which is same as : \(\color{green}{3<x\le 4}\)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
and of course the last one, \(\color{green}{x >= 5}\)
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
sorry for being away, I'm here again :)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
np :) see if above stuff makes sense
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
it makes sense but why in the final answer they used "or" not "and" "," "then" or anything else dom K: {xx<2 or 3<x<=4 or x>=5}
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
yeah we always combine domain with "or" why ? cuz its meaningful. let me ask u a q
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
suppose we write : x < 2 and x >=5
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
for the domain it is ALWAYS "or" ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
is that possible ? can x be BOTH less than 2 and greater than 5 at the SAME time ha ?
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
yes, it is not possible
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
is "1" less than 2 and greater than "5" ?
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
yeah, but if we put it like this : either "1" is less than 2 or greater than "5"
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
how meaningful it is, so while phrasing domain also, we use commonsense aswell :)
 one year ago

moongazerBest ResponseYou've already chosen the best response.1
yes, Thank you very much for helping me :)
 one year ago

ganeshie8Best ResponseYou've already chosen the best response.1
np i learned as well. i forgot these long back in college... i enjoyed going thru these again.. thnks you too :)
 one year ago
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