已知关于x的一元二次函数f(x)=ax
2-4bx+1.
(1)设集合P={1,2,3}和Q={-1,1,2,3,4},分别从集合P和Q中随机取一个数作为a和b,求函数y=f(x)在区间[1,+∞)上是增函数的概率;
(2)设点(a,b)是区域
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内的随机点,求y=f(x)在区间[1,+∞)上是增函数的概率.
考点分析:
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