求多项式(1)-3x²+3xy-2/1y²与-2/1x²+4xy-2/3y²的差 下面还有.(2)计算(3x-2y)²(2y-3x)³(2y-3x)4次方 (结果用幂的形式表示)(3)计算:(-x)³(x²) 5次方x-(-x 4次方)²(-
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![求多项式(1)-3x²+3xy-2/1y²与-2/1x²+4xy-2/3y²的差 下面还有.(2)计算(3x-2y)²(2y-3x)³(2y-3x)4次方 (结果用幂的形式表示)(3)计算:(-x)³(x²) 5次方x-(-x 4次方)²(-](/uploads/image/z/2545563-3-3.jpg?t=%E6%B1%82%E5%A4%9A%E9%A1%B9%E5%BC%8F%EF%BC%881%EF%BC%89-3x%26sup2%3B%2B3xy-2%2F1y%26sup2%3B%E4%B8%8E-2%2F1x%26sup2%3B%2B4xy-2%2F3y%26sup2%3B%E7%9A%84%E5%B7%AE+%E4%B8%8B%E9%9D%A2%E8%BF%98%E6%9C%89.%EF%BC%882%EF%BC%89%E8%AE%A1%E7%AE%97%EF%BC%883x-2y%29%26%23178%3B%282y-3x%29%26%23179%3B%282y-3x%294%E6%AC%A1%E6%96%B9+++%28%E7%BB%93%E6%9E%9C%E7%94%A8%E5%B9%82%E7%9A%84%E5%BD%A2%E5%BC%8F%E8%A1%A8%E7%A4%BA%EF%BC%89%EF%BC%883%EF%BC%89%E8%AE%A1%E7%AE%97%EF%BC%9A%28-x%29%26%23179%3B%28x%26%23178%3B%29+5%E6%AC%A1%E6%96%B9x-%28-x+4%E6%AC%A1%E6%96%B9%EF%BC%89%26%23178%3B%EF%BC%88-)
求多项式(1)-3x²+3xy-2/1y²与-2/1x²+4xy-2/3y²的差 下面还有.(2)计算(3x-2y)²(2y-3x)³(2y-3x)4次方 (结果用幂的形式表示)(3)计算:(-x)³(x²) 5次方x-(-x 4次方)²(-
求多项式(1)-3x²+3xy-2/1y²与-2/1x²+4xy-2/3y²的差 下面还有.
(2)计算(3x-2y)²(2y-3x)³(2y-3x)4次方 (结果用幂的形式表示)
(3)计算:(-x)³(x²) 5次方x-(-x 4次方)²(-x 6次方)
(4)计算:(x-2y)²-(x-2y)(x+2y)
(5)先化解,在求值. (2x-3)(2x+3)-(1-2x)²+(x-1)(x+2),其中x=-2.
大家帮忙做一下,今晚就要,谢谢谢谢!~~~
求多项式(1)-3x²+3xy-2/1y²与-2/1x²+4xy-2/3y²的差 下面还有.(2)计算(3x-2y)²(2y-3x)³(2y-3x)4次方 (结果用幂的形式表示)(3)计算:(-x)³(x²) 5次方x-(-x 4次方)²(-
(1)-3x²+3xy-1/2y²-(-1/2x²+4xy-3/2y²)
=-3x²+3xy-1/2y²+1/2x²-4xy+3/2y²
=x²(-3+1/2)+xy(3-4)+y²(1/2+3/2)
=-5/2x²-xy+2y²
(2)(3x-2y)²(2y-3x)³(2y-3x)4次方
=(2y-3x)(2+3+4)次方
=(2y-3x)9次方
(3)题目表达不清
(4)(x-2y)²-(x-2y)(x+2y)
=(x-2y)(x-2y-x-2y)
=(x-2y)(-4y)
=8y²-4xy
(5)(2x-3)(2x+3)-(1-2x)²+(x-1)(x+2),
=4x²-9-4x²+4x-1+x²+x-2
=x²+5x-12
当x=-2时
x²+5x-12
=(-2)²+5×(-2)-12
=4-10-12
=-18
(1)-3x²+3xy-1/2y²-(-1/2x²+4xy-3/2y²)
=-3x²+3xy-1/2y²+1/2x²-4xy+3/2y²
=x²(-3+1/2)+xy(3-4)+y²(1/2+3/2)
=-5/2x²-xy+2y²
(2)(3x-2...
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(1)-3x²+3xy-1/2y²-(-1/2x²+4xy-3/2y²)
=-3x²+3xy-1/2y²+1/2x²-4xy+3/2y²
=x²(-3+1/2)+xy(3-4)+y²(1/2+3/2)
=-5/2x²-xy+2y²
(2)(3x-2y)²(2y-3x)³(2y-3x)4次方
=(2y-3x)(2+3+4)次方
=(2y-3x)9次方
(3)题目表达不清
(4)(x-2y)²-(x-2y)(x+2y)
=(x-2y)(x-2y-x-2y)
=(x-2y)(-4y)
=8y²-4xy
(5)(2x-3)(2x+3)-(1-2x)²+(x-1)(x+2),
=4x²-9-4x²+4x-1+x²+x-2
=x²+5x-12
当x=-2时
x²+5x-12
=(-2)²+5×(-2)-12
=4-10-12
=-18
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第一题没看懂,你应该加个括号。
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