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inequalities (1 Viewer)

annabackwards

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Multiply both sides by (5-2x)^2
Move everything to one side, collect the like term (5-2x). Factorise everything. Sketch it and you'll see the answer.
 

kr73114

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so what would the solution for x be. or is there no solution?
 

annabackwards

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so what would the solution for x be. or is there no solution?
After doing what i said you'll end up with
(5-2x)(4x^2 - 18x + 19) < 0
Consider 4x^2 - 18x + 19 = 0
Using quadratic formula we find that the solutions are
[ 18 +/- sqrt20 ]/ 2(4) = [9 +/- sqrt5 ]/4
Therefore (5-2x)(4x^2 - 18x + 19) < 0 becomes
(5-2x) (4x - [9 +sqrt5 ] ) (4x - [9 - sqrt5 ] ) < 0
Sketching that you'll see that you'll see the parts below the x axis are
(9 -sqrt5) /4< x <5/2 or x > (9 +sqrt5) /4 which is the solution

Usually they aren't this evil and when you factorise they're nice integrals XD
 

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