已知关于X的代数式(2X+AX-y+6)-(2bx^2-3x+5y-1)的值与x的取值无关,求式子1/3A^3-2B^2-1/4A^3+3B^2的值
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![已知关于X的代数式(2X+AX-y+6)-(2bx^2-3x+5y-1)的值与x的取值无关,求式子1/3A^3-2B^2-1/4A^3+3B^2的值](/uploads/image/z/405113-41-3.jpg?t=%E5%B7%B2%E7%9F%A5%E5%85%B3%E4%BA%8EX%E7%9A%84%E4%BB%A3%E6%95%B0%E5%BC%8F%282X%2BAX-y%2B6%29-%282bx%5E2-3x%2B5y-1%29%E7%9A%84%E5%80%BC%E4%B8%8Ex%E7%9A%84%E5%8F%96%E5%80%BC%E6%97%A0%E5%85%B3%2C%E6%B1%82%E5%BC%8F%E5%AD%901%2F3A%5E3-2B%5E2-1%2F4A%5E3%2B3B%5E2%E7%9A%84%E5%80%BC)
已知关于X的代数式(2X+AX-y+6)-(2bx^2-3x+5y-1)的值与x的取值无关,求式子1/3A^3-2B^2-1/4A^3+3B^2的值
已知关于X的代数式(2X+AX-y+6)-(2bx^2-3x+5y-1)的值与x的取值无关,求式子1/3A^3-2B^2-1/4A^3+3B^2的值
已知关于X的代数式(2X+AX-y+6)-(2bx^2-3x+5y-1)的值与x的取值无关,求式子1/3A^3-2B^2-1/4A^3+3B^2的值
(2x+ax-y+6)-(2bx^2-3x+5y-1)
=2x+ax-y+6-2bx^2+3x-5y+1
=-2bx^2+2x+ax+3x-5y-y+6+1
=-2bx^2+(a+5)x-6y+7
代数式的值与x的取值无关
所以:-2b=0,a+5=0
即:b=0,a=-5
1/3a^3-2b^2-1/4a^3+3b^2
=1/3a^3-1/4a^3+3b^2-2b^2
=1/12a^3+b^2
=1/12*(-5)^3+0^2
=1/12*(-125)
=-125/12
(2x+ax-y+6)-(2bx^2-3x+5y-1)
=2x+ax-y+6-2bx^2+3x-5y+1
=-2bx^2+2x+ax+3x-5y-y+6+1
=-2bx^2+(a+5)x-6y+7
代数式的值与x的取值无关
所以:-2b=0,a+5
1/3a^3-2b^2-1/4a^3+3b^2
=1/3a^3-1/4a^3+3b^2-2b^2
=1/12a^3+b^2
=1/12*(-5)^3+0^2
=1/12*(-125)
=-125/12
(2X+AX-y+6)-(2bx^2-3x+5y-1)
=2X+AX-y+6-2bx^2+3x-5y+1
=2bx^2+2x+ax+3x-5y-y+6+1
=-2bx^2+(a+5)x-6y+7
∵值与X的取值无关
∴-2b=0 a+5=0
b=0 a=-5
1/3a^3-2b^2-1/4a^3...
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(2X+AX-y+6)-(2bx^2-3x+5y-1)
=2X+AX-y+6-2bx^2+3x-5y+1
=2bx^2+2x+ax+3x-5y-y+6+1
=-2bx^2+(a+5)x-6y+7
∵值与X的取值无关
∴-2b=0 a+5=0
b=0 a=-5
1/3a^3-2b^2-1/4a^3+3b^2
=1/3a^3-1/4a^3+3b^2-2b^2
=1/12a^3+b^2
=1/12*(-5)^3+0^2
=1/12*(-125)
=-125/12
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