要使x(x^2+a)+3x-2b=x^3+5x+4恒成立,则a=_,b_.已知2^(m+3)·3^(2n-3)=12^m,求n^m的值.
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![要使x(x^2+a)+3x-2b=x^3+5x+4恒成立,则a=_,b_.已知2^(m+3)·3^(2n-3)=12^m,求n^m的值.](/uploads/image/z/7647956-44-6.jpg?t=%E8%A6%81%E4%BD%BFx%28x%5E2%2Ba%29%2B3x-2b%3Dx%5E3%2B5x%2B4%E6%81%92%E6%88%90%E7%AB%8B%2C%E5%88%99a%3D_%2Cb_.%E5%B7%B2%E7%9F%A52%5E%28m%2B3%29%C2%B73%5E%282n-3%29%3D12%5Em%2C%E6%B1%82n%5Em%E7%9A%84%E5%80%BC.)
要使x(x^2+a)+3x-2b=x^3+5x+4恒成立,则a=_,b_.已知2^(m+3)·3^(2n-3)=12^m,求n^m的值.
要使x(x^2+a)+3x-2b=x^3+5x+4恒成立,则a=_,b_.已知2^(m+3)·3^(2n-3)=12^m,求n^m的值.
要使x(x^2+a)+3x-2b=x^3+5x+4恒成立,则a=_,b_.已知2^(m+3)·3^(2n-3)=12^m,求n^m的值.
(1) 解方程,对应项相等,a=2,b=-2
(2) 12^m=2^2m·3^m=2^(m+3)·3^(2n-3),所以对应项相等,2m=m+3,m=2n-3,
所以m=3,n=3,n^m=27