1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
IrinaVladis [17]
3 years ago
6

Which is an irrational number?

Mathematics
1 answer:
erica [24]3 years ago
5 0

A. is the answer it can't be rational

Step-by-step explanation:

√21 is irrational.

Let's assume that √21 is rational. So √21 can be expressed in the form p/q form.

p/q is the reduced form of rational number so p and q have no common factors other than 1, i.e. they are co-prime numbers.

√21 = p/q

21 = p^2/q^2... (squaring both the sides)

21q^2 = p^2

p^2 is even. p^2 is a factor of 2...(1)

p=2t p^2=4t^2 t belongs to I

2q^2 = 4t^2 (2q^2=p^2)

q^2 = 2t^2

q^2 is even

q is even

2 is a factor of q.

From the statements (1) and (2), 2 is a common factor of p and q both.

This is contradictory because in p/q, we have assumed that p and q have no common factors other than 1.

That is, our assumption that √21 is rational is wrong.

Therefore, √21 is irrational.

You might be interested in
PLZZ HELP I WILL GIVE YOU 30 POINTS!!!!!<br> ​ <br> ​ <br> ​
elena-s [515]
7 cheese:8
7 pepperonis:3
7 veggie:1
8 cheese:4
8 pepperoni :5
8 veggie:3
7 0
3 years ago
Determine the location and values of the absolute maximum and absolute minimum for given function : f(x)=(‐x+2)4,where 0&lt;×&lt
brilliants [131]

Answer:

Where 0 < x < 3

The location of the local minimum, is (2, 0)

The location of the local maximum is at (0, 16)

Step-by-step explanation:

The given function is f(x) = (x + 2)⁴

The range of the minimum = 0 < x < 3

At a local minimum/maximum values, we have;

f'(x) = \dfrac{(-x + 2)^4}{dx}  = -4 \cdot (-x + 2)^3 = 0

∴ (-x + 2)³ = 0

x = 2

f''(x) = \dfrac{ -4 \cdot (-x + 2)^3}{dx}  = -12 \cdot (-x + 2)^2

When x = 2, f''(2) = -12×(-2 + 2)² = 0 which gives a local minimum at x = 2

We have, f(2) = (-2 + 2)⁴ = 0

The location of the local minimum, is (2, 0)

Given that the minimum of the function is at x = 2, and the function is (-x + 2)⁴, the absolute local maximum will be at the maximum value of (-x + 2) for 0 < x < 3

When x = 0, -x + 2 = 0 + 2 = 2

Similarly, we have;

-x + 2 = 1, when x = 1

-x + 2 = 0, when x = 2

-x + 2 = -1, when x = 3

Therefore, the maximum value of -x + 2, is at x = 0 and the maximum value of the function where 0 < x < 3, is (0 + 2)⁴ = 16

The location of the local maximum is at (0, 16).

5 0
3 years ago
If Seth used 4 ounces of black beans, how many beans did he use altogether?​
musickatia [10]

Answer: 4 Ounces.

Step-by-step Explanation: I don't know the full context of the problem, but if Seth used 4 ounces, that means that he used 4 ounces all together.

6 0
2 years ago
A fitted multiple regression equation is Y = 28 + 5X1 - 4X2 + 7X3 + 2X4. When X1 increases 2 units and X2 increases 2 units as w
ad-work [718]

Answer:

A. Increase by 2

Step-by-step explanation:

Given that a  fitted multiple regression equation is

Y = 28 + 5X_1 -4X_2 + 7X_3 + 2X_4

This is a multiple regression line with dependent variable y and independent variables x1, x2, x3 and x4

The coefficients of independent variables represent the slope.

In other words the coefficients represent the rate of change of y when xi is changed by 1 unit.

Given that x3 and x4 remain unchanged and x1 increases by 2 and x2 by 2 units

Since slope of x1 is 5, we find for one unit change in x1 we can have 5 units change in y

i.e. for 2 units change in x1, we expect 10 units change in Y

Similarly for 2 units change in x2, we expect -2(4) units change in Y

Put together we have

10-8 =2 change in y

Since positive 2, there is an increase by 2

A. Increase by 2

5 0
3 years ago
PLEASE 25 POINTS!!!!!!
Rufina [12.5K]
-4.9t²+7.5t+1.8=2.1
-4.9t²+7.5t-0.3=0

t=-7.5±√(56.25-4*-4.9*-.3)/-2*4.9

t=-7.5±√(44.49/-9.8

t=(-7.5±6.67)/-9.8

t=-.83/-9.8 = .085 or t= -14.17/-9.8 = 1.446
8 0
3 years ago
Read 2 more answers
Other questions:
  • What is the measure of a base angle of an isosceles triangle if the measure of the vertex tangle is 38 degrees and the two congr
    11·1 answer
  • Help me with this problem pleas
    14·2 answers
  • what is the probability of randomly choosing a penny and a nickel from a cup of coins that contains a penny nickel a dime and a
    12·1 answer
  • A conference will take place in a large hotel meeting room. The organizers of the conference have created a drawing for how to a
    9·1 answer
  • DESCRIBE A RULE YOU COULD USE TO FIND
    8·2 answers
  • 1. Francis was biking up the hill in the image to the right. The hill made a 45° angle with the
    9·1 answer
  • Last year 12 records in his collection now he has 15 records what is his percent increase of his Collection
    6·1 answer
  • How do I get from step 2 to step 3?
    9·2 answers
  • Help
    11·1 answer
  • In 2021, the Internal Revenue Service (IRS) decreased the deductible mileage cost to 56 cents from 57.5 cents. Find the percent
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!