Final answer:
For the given polynomial p(x)=x3−ax with a>0: It has three x-intercepts at x=0,x=a, and x=−a. There is one local minimum at x=−3a and two local maxima at x=3a. This leads to the correct answer: c) 3 x-intercepts, 1 local minimum, and 2 local maxima.
This correct answer is c)
Step-by-step explanation:
Step-by-step explanation:
1. X-intercepts:
The polynomial p(x)=x3−ax has three x-intercepts when a>0: x=0, x=a, and x=−a.
2. Local Extrema:
- The derivative of p(x) is p′ (x)=3x2−a.
- Setting 3x2−a=0 gives x= √a/3 and x= -√a/3.
- Checking the sign of p′ (x) around these points, we find:
- If a>0, then p′ (x)>0 for x<− √a/3, p′ (x)<0 for − √a/3 <x< √a/3, and p′ (x)>0 for x> √a/3
Therefore, there is a local minimum at x=− √a/3 and a local maximum at
x= √a/3.
In summary, the characteristics of the polynomial p(x)=x3−ax match the description in option c).
This correct answer is c)