Question 408988
(-4-2x^5+9x^7-8x^6)-(x^6+4x^5+4+3x^7)
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{{{(-4-2x^5+9x^7-8x^6)-(x^6+4x^5+4+3x^7)}}}
= {{{-4 - 2x^5 + 9x^7 - 8x^6 - x^6 -4x^5 - 4 - x^7 }}}
= {{{8x^7 - 9x^6 - 6x^5 - 8}}}