Consider the following equation. cos x = x3 (a) Prove that the equation has at least one real root. f(x) = cos x − x3 is continu

Answer:

Detailed solution:

Given:

The problem to solve is:

Convert the equation into the standard quadratic form , where represent constants.

So, by adding to both sides, we get:

Note that .

The roots of this quadratic are found by applying the quadratic formula given as:

Substitute into the formula and calculate for .

Hence, the roots are:

Explanation:

Step-by-step clarification:

Referring to step 6

(b² — 4ac) / 4a² = (x + b/2a)²

The mistake in the question is that it should be (x + b/2a)²

According to step 7

±√(b² —4ac) /2a = x + b/2a

The error in the question is that it should be divided by 2a, not 1a.

1. The transition from step 6 to step 7 involves taking the square roots of both sides

(b² — 4ac) / 4a² = (x + b/2a)²

Taking the square of both sides

√(b²—4ac) / √4a² = √(x + b/2a)²

√(b²—4ac) / 2a = x + b/2a

This forms step 7 correctly.

Next, subtracting b/2a from both sides

√(b²—4ac) / 2a - b/2a= x + b/2a -b/2a

√(b²—4ac) / 2a — b/2a = x

(√(b²—4ac)  — b)/2a = x

x = [—b ± √(b²—4ac)] / 2a

This gives the desired formula.

The discriminant is D = b²—4ac.

Let the events be defined as follows:
A=Nathan suffers from an allergy
~A=Nathan does not suffer from an allergy
T=Nathan receives a positive test result
~T=Nathan does not receive a positive test result

According to the provided data,
P(A)=0.75 [ probability indicating that Nathan is allergic ]
P(T|A)=0.98 [ probability of obtaining a positive test result if Nathan is allergic to Penicillin]

We aim to calculate the probability that Nathan is both allergic and tests positive
P(T n A)

Using the definition of conditional probability,
P(T|A)=P(T n A)/P(A)
By substituting the known values,
0.98 = P(T n A) / 0.75
We then solve for P(T n A)
P(T n A) = 0.75*0.98 = 0.735

Hope this assists you!!

Answer: 26.3 mm

Step-by-step explanation:

The two-standard deviations rule for outliers states that any value lying outside two standard deviations from the average is considered an outlier.

Given that the Mean is 23.5 millimeters (mm) and the standard deviation is 1.4 mm

The maximum thickness that should be reviewed = mean + 2 (standard deviation)

= 23.5 + 2(1.4)

= 23.5 + 2.8

= 26.3 mm

therefore, the maximum thickness warranting machine configuration review by the statistician = 26.3 mm.

Answer:

Step-by-step explanation:

Given that lines l and m are parallel and there is a transversal cutting through these lines.

5). (9x + 2)° = 119° [by alternate interior angles]

    9x = 117 ⇒ x = 13

6). (12x - 8)° + 104° = 180°

     12x = 180 - 96

     x = ⇒ x = 7

7). (5x + 7) = (8x - 71) [by alternate exterior angles]

    8x - 5x = 71 + 7

    3x = 78

     x = 26

8). (4x - 7) = (7x - 61) [by corresponding angles]

    7x - 4x = -7 + 61

    3x = 54

     x = 18

9). (9x + 25) = (13x - 19) [by corresponding angles]

    13x - 9x = 25 + 19

    4x = 44

     x = 11

   (13x - 19)° + (17y + 5)° = 180° [linear pairs of angles sum to supplementary]

    (13×11) - 19 + 17y + 5 = 180

    129 + 17y = 180

    17y = 180 - 129

     y = 3

10). (3x - 29) + (8y + 17) = 180 [linear pairs of angles sum to supplementary]

     3x + 8y = 180 + 12

     3x + 8y = 192 -----(1)

     (8y + 17) = (6x - 7) [by alternate exterior angles]

     6x - 8y = 24

     3x - 4y = 12 -----(2)

     From equation (1) subtract equation (2)

     (3x + 8y) - (3x - 4y) = 192 - 12

     12y = 180

     y = 15

     Plugging into equation (1),

     3x + 8(15) = 192

     3x + 120 = 192

    x = 24

11). (3x + 49)° = (7x - 23)° [by corresponding angles]

    7x - 3x = 49 + 23

    4x = 72 ⇒ x = 18

    (11y - 1)° = (3x)° [by corresponding angles]

    11y = 3×18 + 1

     11y = 55 ⇒ y = 5

12). (5x - 38)° = (3x - 4)° [by corresponding angles]

     5x - 3x = 38 - 4

     2x = 34

     x = 17

     (7y - 20)° + (5x - 38)° + 90° = 180°

     [The angles within a triangle sum to 180°]

     7y + 5x - 58 = 90

     5x + 7y = 148

     5×17 + 7y = 148

     85 + 7y = 148

     7y = 148 - 85

     y =