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已知幂函数
求
参考答案:由题意,函数\(f\left( x \right) = {x^{4m - {m^2}}}\)(\(m \in Z\))的图像关于\(y\)轴对称,且\(f\left( 2 \right) < f\left( 3 \right)\),所以在区间\((0, + \infty )\)为单调递增函数,所以\({m^2} - 4m < 0\),解得\(0 < m < 4\),由\(m \in Z\),\(m = 1,2,3\)。又函数\(f\left( x \right) = {x^{4m - {m^2}}}\)的图像关于\(y\)轴对称,所以\(4m - {m^2}\)为偶数,所以\(m = 2\),所以\(f\left( x \right) = {x^4}\).