计算:(1)(n+1)(n+3)(n+5) ;(2)-5x(-x²+2x+1)-(2x+3)(5-x²)要详细过程
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计算:(1)(n+1)(n+3)(n+5) ;(2)-5x(-x²+2x+1)-(2x+3)(5-x²)要详细过程
计算:(1)(n+1)(n+3)(n+5) ;(2)-5x(-x²+2x+1)-(2x+3)(5-x²)
要详细过程
计算:(1)(n+1)(n+3)(n+5) ;(2)-5x(-x²+2x+1)-(2x+3)(5-x²)要详细过程
(1)
(n+1)(n+3)(n+5)
=(n²+4n+3)(n+5)
=n⁴+5n+4n²+20n+3n+15
=n⁴+4n²+28n+15
(2)-5x(-x²+2x+1)-(2x+3)(5-x²)
=5x³-10x²-5x-(10x-2x³+15-3x²)
=5x³-10x²-5x-10x+2x³-15+3x²
=5x³+2x³+3x²-10x²-5x-10x-15
=7x³-7x²-15x-15
(n+1)(n+3)(n+5) =(n^2+4n+3)(n+5) =n^3+5n^2+4n^2+20n+3n+15 =n^3+9n^2+23n+15 -5x(-x²+2x+1)-(2x+3)(5-x²) =5x^3-10x-5x-(10x-2x^3+15-3x^2) =7*x^3-25*x-15+3*x^2
(n+1)(n+3)(n+5)
=(n²+4n+3)(n+5)
=n³+5n²+4n²+20n+3n+15
=n³+9n²+23n+15
(2)-5x(-x²+2x+1)-(2x+3)(5-x²)
=5x³-10x²-5x-(10x-2x...
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(n+1)(n+3)(n+5)
=(n²+4n+3)(n+5)
=n³+5n²+4n²+20n+3n+15
=n³+9n²+23n+15
(2)-5x(-x²+2x+1)-(2x+3)(5-x²)
=5x³-10x²-5x-(10x-2x³+15-3x²)
=5x³-10x²-5x-10x+2x³-15+3x²
=5x³+2x³-10x²+3x²-5x-10x-15
=7x³-7x²-15x-15
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