函数f(x)=a-b^(3x^2-5x-2)的单调增区间是

问题描述:

函数f(x)=a-b^(3x^2-5x-2)的单调增区间是
b>1

f(x)=a-b^(3x^2-5x-2)
∵b>1
∴当3x^2-5x-2单调减时,b^(3x^2-5x-2)单调减,f(x)=a-b^(3x^2-5x-2)单调增
又:g(x)=3x^2-5x-2开口向上,对称轴x=-(-5)/(2*3) = 5/6
∴x<5/6时b^(3x^2-5x-2)单调减
∴f(x)=a-b^(3x^2-5x-2)单调增区间是(-∞,5/6)