Question

1. which of the following is a fourth degree polynomial function? select all that apply.
a. f(x)= 4x^3 - x^2 + 2x - 7
b. f(x)= 5-x^4
c. f(x)= 1 / 2x^4 + x^2 -5
d. f(x)= 3x^4 + 2x^3 -4x +1
2. which function below has the end behavior f(x) approaches neg. infinity as x approaches infinity and f(x) approaches infinity as x approaches neg. infinity?
a. f(x)= 3x^5 - 2x^2 + 5x -1
b. f(x)= 5x^2 - 7 +6
c. f(x)= -x^3 -4x^2 +x
d. f(x)= -3x^4 + 2x^3 +6x - 10
3. the graph of a polynomial function has 3 turning points. what do you know about the degree and the extrema of this polynomial?
a. the polynomial is degree 3 and has 3 extrema
b. the polynomial is at least degree 3 and has 4 extrema
c. the polynomial is degree 4 and has 4 extrema
d. the polynomial is at least degree 4 and has 3 extrema
4. what is the maximum for the graphed function on the interval [-1,3]?
(idk if the graph is important but it starts out increasing from the left, theres an arrow at the end so i guess that means its infinite, crosses the x axis at (-1,0), there's a turning point at (1,3.5) and it starts decreasing, another turning point at (3,1.5) it starts increasing again, another turning point at (5,4) then decreases and keeps going past the graph.)
a. 1.5
b. 2
c. 3.5
d. 4
my answers for 1 are A and D, my answer for 2 is A, my answer for 3 is C, and my answer for 4 is C. are these right? i'm really stumped.

Answer 1

#1. is B and D -- 4 is highest exponent
#2. C (A is just the opposite)
#3. D
#4. C is correct

Answer 2

thank you sm dude

Answer 3

oobleck is correct

Answer 4

Okay, they're right for the practice, I've got the qc below:

1) C. The function is a polynomial. The degree is 4 and the leading coefficient is -3

2) B. f (x) -> -∞ as x -> -∞; f (x) -> -∞ as x -> ∞
(It's negative, negative, negative, positive)

3) C. 5

4) A. (-2, -2) is a local minimum
C. (4, 4) is the global maximum