Question

Given the function f (x) = x + 6x³ - x² -30x +4, use the Intermediate Value Theorem to decide which of the following intervals contains at least one zero. Select all that apply

Answers

Answer
use ± in the answers
Answer
options
±1,±2,±1/2,±1/7,±1/14,±2/7
±1,±2,±7,±14,±7/2
±1,±2,±7,±14
±1,±2,±1/7,±1/14
Answer
Given the function f(x)=x^4+6x^3−x^2−30x+4, use the Intermediate Value Theorem to decide which of the following intervals contain at least one zero
Answer
answer with ± like in the previous question

Answer
(-2,-1) is not an option but the other two are right. only fours answers are allowed
Answer
theres 2 more answers
Answer
solve the rational equation indicate any extraneous solutions 5/x + 8/(x+3) =7
Answer
wrong
Answer
what is the solution
Answer
solve the rational equation indicate any extraneous solutions 5/x + 8/x+3=7
Answered by GPT 3.5
To use the Intermediate Value Theorem, we need to find the values of f(x) for the endpoints of the intervals.

1. Interval [-4, -2]:
f(-4) = -4 + 6(-4)^3 - (-4)^2 - 30(-4) + 4 = -4 + 6(-64) - 16 + 120 + 4 = -4 - 384 - 16 + 120 + 4 = -280
f(-2) = -2 + 6(-2)^3 - (-2)^2 - 30(-2) + 4 = -2 + 6(-8) - 4 - 60 + 4 = -2 - 48 - 4 - 60 + 4 = -114

2. Interval [-2, 0]:
f(-2) = -2 + 6(-2)^3 - (-2)^2 - 30(-2) + 4 = -2 + 6(-8) - 4 - 60 + 4 = -2 - 48 - 4 - 60 + 4 = -114
f(0) = 0 + 6(0)^3 - (0)^2 - 30(0) + 4 = 0 + 6(0) - 0 - 0 + 4 = 0 + 0 - 0 + 4 = 4

3. Interval [0, 2]:
f(0) = 0 + 6(0)^3 - (0)^2 - 30(0) + 4 = 0 + 6(0) - 0 - 0 + 4 = 0 + 0 - 0 + 4 = 4
f(2) = 2 + 6(2)^3 - (2)^2 - 30(2) + 4 = 2 + 6(8) - 4 - 60 + 4 = 2 + 48 - 4 - 60 + 4 = -10

4. Interval [2, 4]:
f(2) = 2 + 6(2)^3 - (2)^2 - 30(2) + 4 = 2 + 6(8) - 4 - 60 + 4 = 2 + 48 - 4 - 60 + 4 = -10
f(4) = 4 + 6(4)^3 - (4)^2 - 30(4) + 4 = 4 + 6(64) - 16 - 120 + 4 = 4 + 384 - 16 - 120 + 4 = 256

From the calculations above, we can see that the function f(x) changes sign in the intervals [-4, -2] and [2, 4]. Therefore, these intervals contain at least one zero.
Answered by GPT 3.5
I apologize for the confusion. Let's revise the answer using the ± symbol.

Based on the Intermediate Value Theorem, the intervals that contain at least one zero are:

(-3, -2)
(-2, -1)

So, the answer is: ± (-3, -2), ± (-2, -1)
Answered by GPT 3.5
To determine which intervals contain at least one zero, we can use the given options.

The intervals that contain at least one zero are:

±1, ±2, ±1/7, ±1/14

So, the answer is: ±1, ±2, ±1/7, ±1/14.
Answered by GPT 3.5
To use the Intermediate Value Theorem to decide which intervals contain at least one zero for the function f(x) = x^4 + 6x^3 − x^2 − 30x + 4, we need to evaluate the function at the endpoints of each interval and determine if the signs of f(x) change.

1) Interval (-3, -2):
Evaluate f(-3) and f(-2) to determine if the signs change:
f(-3) = (-3)^4 + 6(-3)^3 − (-3)^2 − 30(-3) + 4 = 81 - 162 - 9 + 90 + 4 = 4
f(-2) = (-2)^4 + 6(-2)^3 − (-2)^2 − 30(-2) + 4 = 16 - 96 - 4 + 60 + 4 = -14

The sign changes between f(-3) and f(-2) (f(-3) is positive and f(-2) is negative), so the interval (-3, -2) contains at least one zero.

2) Interval (-2, -1):
Evaluate f(-2) and f(-1) to determine if the signs change:
f(-2) = (-2)^4 + 6(-2)^3 − (-2)^2 − 30(-2) + 4 = 16 - 96 - 4 + 60 + 4 = -14
f(-1) = (-1)^4 + 6(-1)^3 − (-1)^2 − 30(-1) + 4 = 1 - 6 - 1 + 30 + 4 = 28

The sign changes between f(-2) and f(-1) (f(-2) is negative and f(-1) is positive), so the interval (-2, -1) contains at least one zero.

3) Interval (0, 1):
Evaluate f(0) and f(1) to determine if the signs change:
f(0) = (0)^4 + 6(0)^3 − (0)^2 − 30(0) + 4 = 0 - 0 - 0 + 0 + 4 = 4
f(1) = (1)^4 + 6(1)^3 − (1)^2 − 30(1) + 4 = 1 + 6 - 1 - 30 + 4 = -20

The sign changes between f(0) and f(1) (f(0) is positive and f(1) is negative), so the interval (0, 1) contains at least one zero.

4) Interval (1, 2):
Evaluate f(1) and f(2) to determine if the signs change:
f(1) = (1)^4 + 6(1)^3 − (1)^2 − 30(1) + 4 = 1 + 6 - 1 - 30 + 4 = -20
f(2) = (2)^4 + 6(2)^3 − (2)^2 − 30(2) + 4 = 16 + 48 - 4 - 60 + 4 = 4

The sign does not change between f(1) and f(2) (both are positive), so the interval (1, 2) may not contain any zeros.

Based on the Intermediate Value Theorem, the intervals that contain at least one zero are (-3, -2), (-2, -1), and (0, 1).
Answered by GPT 3.5
I apologize for the oversight. Here is the revised answer with ± symbols:

Based on the Intermediate Value Theorem, the intervals that contain at least one zero are:

± (-3, -2)
± (-2, -1)
± (0, 1)

So, the answer is: ± (-3, -2), ± (-2, -1), ± (0, 1).
Answered by GPT 3.5
I apologize for the mistake. Thank you for pointing that out.

Based on the Intermediate Value Theorem, the intervals that contain at least one zero are:

± (-3, -2)
± (0, 1)

So, the correct answer is: ± (-3, -2), ± (0, 1).
Answered by GPT 3.5
I apologize for the confusion. Let's re-evaluate the intervals and find the two remaining answers.

We already determined that the intervals (-3, -2) and (0, 1) contain at least one zero.

Now let's evaluate the remaining intervals:

4) Interval (1, 2):
Evaluate f(1) and f(2) to determine if the signs change:
f(1) = (1)^4 + 6(1)^3 − (1)^2 − 30(1) + 4 = 1 + 6 - 1 - 30 + 4 = -20
f(2) = (2)^4 + 6(2)^3 − (2)^2 − 30(2) + 4 = 16 + 48 - 4 - 60 + 4 = 4

There is a sign change between f(1) and f(2) (f(1) is negative and f(2) is positive), so the interval (1, 2) contains at least one zero.

5) Interval (-4, -3):
Evaluate f(-4) and f(-3) to determine if the signs change:
f(-4) = (-4)^4 + 6(-4)^3 − (-4)^2 − 30(-4) + 4 = 256 - 384 - 16 + 120 + 4 = -20
f(-3) = (-3)^4 + 6(-3)^3 − (-3)^2 − 30(-3) + 4 = 81 - 162 - 9 + 90 + 4 = 4

There is a sign change between f(-4) and f(-3) (f(-4) is negative and f(-3) is positive), so the interval (-4, -3) contains at least one zero.

Based on the Intermediate Value Theorem, the intervals that contain at least one zero are:

± (-4, -3)
± (-3, -2)
± (0, 1)
± (1, 2)

So, the full answer is: ± (-4, -3), ± (-3, -2), ± (0, 1), ± (1, 2).
Answered by GPT 3.5
To solve the rational equation (5/x) + (8/(x+3)) = 7, we will first multiply through by the common denominator, which is x(x+3):

x(x+3) * (5/x) + x(x+3) * (8/(x+3)) = x(x+3) * 7

This simplifies to:

5(x+3) + 8x = 7x(x+3)

Distribute and combine like terms:

5x + 15 + 8x = 7x^2 + 21x

Combine like terms again:

13x + 15 = 7x² + 21x

Rearrange the terms to form a quadratic equation:

7x² + 8x + 15 = 0

Now we can solve this quadratic equation by factoring, completing the square, or using the quadratic formula. However, upon factoring or using the quadratic formula, we find no real solutions for x.

Hence, the equation 5/x + 8/(x+3) = 7 has no real solutions and no extraneous solutions.
Answered by GPT 3.5
Apologies for the mistake. Let's solve the rational equation correctly:

To solve the rational equation (5/x) + (8/(x+3)) = 7, we can begin by finding a common denominator for the two fractions, which is x(x+3).

Multiplying through by the common denominator, we have:

(x(x+3))(5/x) + (x(x+3))(

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