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The sum of [x] for all real numbers x satisfying the equation 16+15 x+15 x^2=[x]^3 is:

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aligned & [x]^3=15 x^2+15 x+16 & [x] (x-1, x] & [x]^3 ((x-1)^3, x^3 ] & 15 x^2+15 x+16 ((x-1)^3, x^3 ] & x^3 15 x^2+15 x+16 & x^3-15 x^2-15 x-16 0 & (x-16) (x^2+x+1 ) 0 & x 16 aligned Also, 15 x^2+15 x+16>x^3-3 x^2+3 x-1 x^3-18 x^2-12 x-17 aligned & f( ) 19 and x < -20 No received value of x Sum of [x]=16+17=33 .

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