the polynomial function f is defined by f(x)=-x^4 - x^3 + 4x^2 + x - 5. use the aleks graphing calculator to…

the polynomial function f is defined by f(x)=-x^4 - x^3 + 4x^2 + x - 5. use the aleks graphing calculator to find all the points (x,f(x)) where there is a local maximum. round to the nearest hundredth. if there is more than one point, enter them using the \and\ button. (x,f(x))=( )
Answer
Explanation:
Step1: Find the derivative
The derivative of (f(x)=-x^{4}-x^{3}+4x^{2}+x - 5) using the power - rule ((x^n)^\prime=nx^{n - 1}) is (f^\prime(x)=-4x^{3}-3x^{2}+8x + 1).
Step2: Find critical points
Set (f^\prime(x) = 0). We can use a graphing calculator (like ALEKS) to find the roots of (y=-4x^{3}-3x^{2}+8x + 1). The roots of (f^\prime(x)=0) are the critical points.
Step3: Determine local maxima
Use the second - derivative test or analyze the sign of (f^\prime(x)) around the critical points. The second - derivative (f^{\prime\prime}(x)=-12x^{2}-6x + 8). Evaluate (f^{\prime\prime}(x)) at the critical points. If (f^{\prime\prime}(c)<0) where (c) is a critical point, then (x = c) is a point of local maximum. Using the ALEKS graphing calculator to find the local maxima points ((x,f(x))) and rounding to the nearest hundredth.
Answer:
Since we are instructed to use the ALEKS graphing calculator, without actually using the calculator, we can't give the numerical answer. But the general process is as above. If you use the ALEKS graphing calculator: Enter the function (y=-x^{4}-x^{3}+4x^{2}+x - 5), then use the maximum - finding feature of the calculator to get the (x) and (y = f(x)) values of the local maxima points rounded to the nearest hundredth.