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    Help? How do I go about findig x from this negative cubic? Please show me the steps so I can learn from them?
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    Well if -2x^3+16=0 the 2x^3-16=0 as well (times each side by -1)

    Hence you should be OK now?
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    (Original post by Bhansongal98)
    Help? How do I go about findig x from this negative cubic? Please show me the steps so I can learn from them?
    Recall that 2x^-3 = 2*(1/x^3). You should have everything you need to solve it now.

    (Original post by nerak99)
    Well if -2x^3+16=0 the 2x^3-16=0 as well (times each side by -1)

    Hence you should be OK now?
    The OP's problem is the negative exponential, not the negative sign.
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    I've got it down to 8x^3 - 1 but I'm struggling to find a factor
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    8x^3-1=0 => 8x^3=1 (=) x^3=1/8 (=) x=1/2


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    (Original post by Bhansongal98)
    I've got it down to 8x^3 - 1 but I'm struggling to find a factor
    0= -2x^-3+16
    (+-2x^-3) 2x^-3=16
    (divide by 2) x^-3=8
    (x^-3= 1/x³) 1/x³=8
    (multiply by x³) 1=8x³
    (divide by 8) 1/8=x³
    (cube root)x=1/2
 
 
 
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