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InequalitySolve each inequality graphically. State the solution and graph the solution: a) (X^3) – (6x^2) +5x+12 >0 b) X/(x^2 -2x-8) >0 |

Re: Inequality1 Attachment(s) I do not know right answer but in my head))) exist this: X/(x^2 -2x-8) >0 for the (x^2 -2x-8) : x = [ 2 +/- square_root( 2^2 - 4*(-8) ) ] / 2 = 1 +/- square_root( 4 + 32 )/2 = = 1 +/- 6/2 = 1 +/- 3 = { 4, -2 } (x1 = 4 and x2 = -2) then we can to write x/(x^2 -2x-8) = x / [ (x - x1)*(x - x2) ] = x / [ (x - 4)*(x + 2) ] I think this x do not equal 4 and -2 because we will have division by zero (but we used this numbers to transform equation) we have x from ( - infinity) to (+ infinity) then case ( x < - 2 ) : (-) /[ (-)*(-) ] < 0 /* because x < 0, x - 4 < 0 , x + 2 < 0 as conclusion from that :: x < - 2 */ case ( -2 < x < 0 ) : (-) /[ (-)*(+) ] > 0 /* because x < 0, x - 4 < 0 , x + 2 > 0 as conclusion from that :: -2 < x < 0 */ case ( 0 < x < 4 ) : (+) /[ (-)*(+) ] < 0 /* because x > 0, x - 4 < 0 , x + 2 > 0 as conclusion from that :: 0 < x < 4 */ case ( 4 < x ) : (+) /[ (+)*(+) ] > 0 /* because x > 0, x - 4 > 0 , x + 2 > 0 as conclusion from that :: 4 < x */ But ! You need to write it in proper form, which is demanded by teacher, book, because I do not know the rules of ... |

Re: InequalityHello, jatt-rockz! Quote:
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