已知函数f(x)=1/3x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是A(0,1/2] B(负无穷,1] C(负无穷,1/2] D[1/2,1]
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![已知函数f(x)=1/3x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是A(0,1/2] B(负无穷,1] C(负无穷,1/2] D[1/2,1]](/uploads/image/z/1324602-18-2.jpg?t=%E5%B7%B2%E7%9F%A5%E5%87%BD%E6%95%B0f%EF%BC%88x%EF%BC%89%3D1%2F3x%26%23179%3B-ax%26%23178%3B%2B%282a-1%29x%2Ba%E5%9C%A8%280%2C1%29%E4%B8%8A%E5%8D%95%E8%B0%83%E9%80%92%E5%87%8F%2C%E5%88%99%E5%AE%9E%E6%95%B0a%E7%9A%84%E5%8F%96%E5%80%BC%E8%8C%83%E5%9B%B4%E6%98%AFA%EF%BC%880%2C1%2F2%5D+B%28%E8%B4%9F%E6%97%A0%E7%A9%B7%2C1%5D+C%28%E8%B4%9F%E6%97%A0%E7%A9%B7%2C1%2F2%5D+D%5B1%2F2%2C1%5D)
已知函数f(x)=1/3x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是A(0,1/2] B(负无穷,1] C(负无穷,1/2] D[1/2,1]
已知函数f(x)=1/3x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是
A(0,1/2] B(负无穷,1] C(负无穷,1/2] D[1/2,1]
已知函数f(x)=1/3x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是A(0,1/2] B(负无穷,1] C(负无穷,1/2] D[1/2,1]
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求导=x^2-2ax+2a-1 =(x-1)(x-2a+1) 0点为1和2a-1开口向上
f(x)=1/3x³-ax²+(2a-1)x+a在(0,1)上单调递减 即在(0,1)上(x-1)(x-2a+1)
已知函数f(x)=(1/3)x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是
要使f(x)在(0,1)上单调递减,就应使不等式f'(x)=x²-2ax+2a-1≦0在(0,1)上恒成立;为此,必
须f'(0)=2a-1≦0,即a≦1/2;又因为f'(1)=1-2a+2a-1≡0;故只需a≦1/2就可以了;即a的取值范围
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已知函数f(x)=(1/3)x³-ax²+(2a-1)x+a在(0,1)上单调递减,则实数a的取值范围是
要使f(x)在(0,1)上单调递减,就应使不等式f'(x)=x²-2ax+2a-1≦0在(0,1)上恒成立;为此,必
须f'(0)=2a-1≦0,即a≦1/2;又因为f'(1)=1-2a+2a-1≡0;故只需a≦1/2就可以了;即a的取值范围
为(-∞,1/2].
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