SOLUTION: Solve: {{{ 2 /(x^2-1) >= -3 }}} Include a sketch to support answer. I isolated x to get{{{sqrt ( 3 )/3}}} and {{{-sqrt( 3 )/3}}} but I don't understand how x is greater th

Algebra ->  Graphs -> SOLUTION: Solve: {{{ 2 /(x^2-1) >= -3 }}} Include a sketch to support answer. I isolated x to get{{{sqrt ( 3 )/3}}} and {{{-sqrt( 3 )/3}}} but I don't understand how x is greater th      Log On


   



Question 553110: Solve:
+2+%2F%28x%5E2-1%29+%3E=+-3+
Include a sketch to support answer.
I isolated x to getsqrt+%28+3+%29%2F3 and -sqrt%28+3+%29%2F3 but I don't understand how x is greater than or equal to sqrt+%283%29%2F3 and less than or equal to -sqrt%28+3+%29%2F3. I also don't know how to do the sketch.

Found 2 solutions by solver91311, stanbon:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!




Multiply both sides by



Multiply both sides by . Don't forget to reverse the sense of the inequality because of multiplying by a number less than zero.



Add 1 to both sides:



Now when you take the root of bothsides, recognize that



Which is to say that



or



Draw a number line. Put a filled in dot at . Make a fat arrow going to the right with an arrowhead indicating it goes on forever. Put a filled in dot at . Make a fat arrow going to the left with an arrowhead indicating it goes on forever.

John

My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism


Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve:
2 /(x^2-1) >= -3
------
x cannot be -1 ; x cannot be +1
------
Draw a number line and plot x = -1 and x = 1
----
-----
Solve the Equality:
2 = -3(x^2-1)
2 = -3x^2+3
3x^2 = 1
x^2 = 1/3
x = +-sqrt(3/3)
------
Plot those values on the number line.
--------------
You now have values at -1, -1/sqrt(3), 1/sqrt(3), +1
Find the solution set by testing a value in each
of the resulting 5 intervals:
----
2 /(x^2-1) > -3
Test x = -10:: 2/(99)> -3 ; true ; solutions in (-oo,-1)
Test x = -3/4 ; 2/(-7/16) > -3 ; false
Test x = 0 ; 2/-1 > -3 ; true ; solutions in [-sqrt(1/3),sqrt(1/3]
Test x = +3/4 ; 2/(-7/15) > false
Test x = 10 ; 2/99 > -3 ; true ; solutions in (1,+oo)
=========================================================
Cheers,
Stan H.
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