Posted: 10/16/2007 7:30:20 PM EDT
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I should know this but I'm just not sure of my answer.. The original question is: ((x^2-3x-18)/(x^2+5x+6))*((x^3-64)/(x^2-16)) I factor it down to this and get stuck.. (((x-6)(x+3))/((x+2)(x+3)))*(((x-4)(x^2+4x+16))/((x+4)(x-4))) Then cancel out to get (((x-6) And then get stuck, cause Towely's an idiot.. Or is that as far as you can go? |
yeah, you cant factor that down anymore |
You sure? I get (x-6) / (x+2) divided by (x+4) / (x^2+4x+16) Then you invert before you multiply which gives you the (x-6)(x+4) / (x+2)(x^2+4x+16) By edging them together you are intending to multiply them and the original equation said they were to be factored then divided. ETA: Oh shit, I thought they were to be divided after being factored so I inverted the second equation. Ma bad. 
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Yes, you caught yourself. To multiply fractions, multiply the numerators and multiply the denominators. To go further, multiply the numerator and the denominator (separately) and then do polynomial long division (with a remainder). |
God I hated PLD. 
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My teacher taught us this new way to do that that was really cool. _______ x-5 _______ x+5 ________ ------ ________+5x-25 ____x^2-5x ----------------- ____x^2____-25 Cross multiply just like regular multiplication. I thought it was cool, pretty simple.  Ignore the __ just used for proper spacing. |