document.write( "Question 1167228: Prove or disprove that h(x)=2x^3+1, where in h: integers (Z) → integers (Z) is a bijective function. \n" ); document.write( "
Algebra.Com's Answer #791854 by ikleyn(52786)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "The map   x ---> 2x^3+1   from integer numbers to integer numbers is injective,  but is not bijective.\r
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\n" ); document.write( "\n" ); document.write( "In other words,  the image of this map does not cover the entire set of integer numbers.\r
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\n" ); document.write( "\n" ); document.write( "For example,  the number  11  does not belong to the image,  since the equation\r
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\n" ); document.write( "\n" ); document.write( "             2x^3 + 1 = 11\r
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\n" ); document.write( "\n" ); document.write( "has no solution in integer numbers (due to obvious reasons).\r
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