Q. f(x)=(2x−3)(x+6)(5x+6) has zeros at x=−6,x=−56, and x=23.What is the sign of f on the interval −6<x<−56 ?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.
Identify Sign Changes: Since f(x) has zeros at x=−6, x=−56, and x=23, we know that the function changes sign at each of these points.
Test Interval: We need to test a value between −6 and −56 to determine the sign of f(x) on that interval. Let's pick x=−5.5, which is between −6 and −56.
Calculate f(−5.5): Plug x=−5.5 into f(x) to see the sign: f(−5.5)=(2(−5.5)−3)((−5.5)+6)(5(−5.5)+6).
Calculate f(−5.5): Plug x=−5.5 into f(x) to see the sign: f(−5.5)=(2(−5.5)−3)((−5.5)+6)(5(−5.5)+6).Calculate each term: (2(−5.5)−3)=−11−3=−14, ((−5.5)+6)=0.5, (5(−5.5)+6)=−27.5+6=−21.5.