计算:(-2a^2b)(2/3ab^3)(-6b^2c^3) (x+y)(x-y)-(x-2y)(x+2y) (3x-2y)^2-(3x-y)(3x+y)还有(x+1)(x-1)(x^2-1)-(x^2+1)^2
问题描述:
计算:(-2a^2b)(2/3ab^3)(-6b^2c^3) (x+y)(x-y)-(x-2y)(x+2y) (3x-2y)^2-(3x-y)(3x+y)还有
(x+1)(x-1)(x^2-1)-(x^2+1)^2
答
的平方+6ab+9b的平方
=(a+3b)²
答
(-2a^2b)(2/3ab^3)(-6b^2c^3)
=8a³b的6次方c³
(x+y)(x-y)-(x-2y)(x+2y)
=x²-y²-x²+4y²
=3y²
(3x-2y)^2-(3x-y)(3x+y)
=9x²-12xy+4y²-9x²+y²
=5y²-12xy
(x+1)(x-1)(x^2-1)-(x^2+1)^2
=(x²-1)(x²-1)-(x²+1)²
=x^4-2x²+1-x^4-2x²-1
=-4x²
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