Q. f(x)=x(4x+9)(x−2)(2x−9)(x+5) has zeros at x=−5,x=−49,x=0,x=2, and x=29.What is the sign of f on the interval 0<x<2 ?Choose 1 answer:(A) f is always positive on the interval.(B) f is always negative on the interval.(C) f is sometimes positive and sometimes negative on the interval.
Factors Sign Analysis: Since f(x) is a product of factors, the sign of f(x) on the interval 0 < x < 2 depends on the sign of each factor in that interval.
Consideration of Zeros: The zero at x=0 doesn't affect the interval 0 < x < 2, because we're looking at values of x that are greater than 0.
Endpoint Consideration: The zero at x=2 is the endpoint of the interval, so we only consider values of x that are less than 2.
Positive Factors: The factors (4x+9), (x−2), (2x−9), and (x+5) are all positive for values of x in the interval 0 < x < 2, because their zeros are outside this interval.
Conclusion: Since all factors are positive in the interval 0 < x < 2, the function f(x) is always positive on this interval.
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