Questions and Answers for Math

Math

What do the letters R, Q, N, and Z mean in math?

The letters R, Q, N, and Z refers to a set of numbers such that: R = real numbers includes all real number [-inf, inf] Q= rational numbers ( numbers written as ratio) N = Natural numbers (all...

Latest answer posted September 7, 2010 12:47 pm UTC

1 educator answer

Math

How do I determine if this equation is a linear function or a nonlinear function?

A linear equation has the following form: y = mx + b where m is the slopeb is the y-intercept. You can also perform a vertical line test. If the line touches your graphed function in more than...

Latest answer posted October 7, 2013 8:13 pm UTC

8 educator answers

Math

Given f(x) and g(x), please find (fog)(X) and (gof)(x) f(x) = 2x   g(x) = x+3   

f(x) = 2x g(x) = x + 3 First let us find (fog)(x) (fog)(x) = f(g(x) = f(x+3) = 2(x+3) = 2x + 6 ==> (fog)(x) = 2x + 6 Now let us find (gof)(x): (gof)(x)...

Latest answer posted August 17, 2010 8:49 am UTC

1 educator answer

Math

How do you place 0.2, 0.22, 0.222, 0.2222, and 0.22222 on a number line? Thank you!

They're already in increasing order, which is obvious. If you want to "prove" it (in quotes because the fact may be considered so basic as to not need proof), you can always write the numbers with...

Latest answer posted October 24, 2012 5:48 am UTC

1 educator answer

Math

What is the common and least multiples of 3 and 6? i want to know how to answer the question!

In arithmetic the least common multiple (LCM) of two numbers a and b is the smallest positive integer that is a multiple of both a and b. So, the multiples of 3 are : 3, 6, 9, 12, ...The multiples...

Latest answer posted September 12, 2010 12:21 pm UTC

1 educator answer

Math

Give a practical example of the use of inverse functions. no

We can view a function as something that maps things of one type to things of another type. The inverse of a function tells you how to get back to the original value. We do this a lot in everyday...

Latest answer posted August 10, 2011 4:01 am UTC

2 educator answers

Math

How do you find the vertex of a function in intercept form?

How do you find the vertex of the graph of a quadratic function written in intercept form? Intercept form is also known as factored form: y=(x-p)(x-q) where p,q are the x-intercepts. One way to...

Latest answer posted February 24, 2015 2:15 am UTC

1 educator answer

Math

Solve for b2:A= 1/2h (b1+b2)  

A = 1/2h(b1+b2) Multiply both sides by 2 2A = h(b1+b2) Multiply both sides by 1/h 2A/h = b1+b2 Add -b1 to both sides 2A/h + -b1 = b2 Answer: b2 = 2A/h - b1

Latest answer posted November 14, 2011 5:49 am UTC

1 educator answer

Math

How do you determine a linear function from a table and graph?

You are asking how to determine a linear function from a table and a graph. Linear functions graph as a straight line, no curves allowed. So, if the graph is a straight line, it is the graph of a...

Latest answer posted March 9, 2011 7:59 pm UTC

2 educator answers

Math

How are limits (Calculus limits) used or applied to daily life? Or applied to the real world problems? I need a...

Real-life limits are used any time you have some type of real-world application approach a steady-state solution. As an example, we could have a chemical reaction in a beaker start with two...

Latest answer posted September 2, 2012 3:00 am UTC

1 educator answer

Math

Determine if its a growth or decay.Then find the percent increase of decrease. 1.y=16(.25)^x 2.y=0.8(1.28)^x...

y= 16(0.25)^x The exponential equation represents an exponential decay because the rate of decay is 0.25 which is less than 1. The general form equation is: y(x)= a(1-r)^x such that r is the decay...

Latest answer posted May 23, 2012 2:05 am UTC

1 educator answer

Math

The equation of a line that is perpendicular to the x-axis and passes through the point (2, -1).

A line that is perpendicular to the x-axis is a vertical like with a slope equal to infinity. A line parallel to it would have the same slope and will also be a vertical line perpendicular to the...

Latest answer posted July 1, 2012 5:40 pm UTC

2 educator answers

Math

The sum of square of two consiquative natural number is 313.find the number?

Let 1 number be `x` . Since the numbers are consecutive, the other number would be `x + 1.` Square both and add together to equal 313. `x^2 + (x+1)^2 = 313` `x^2 + x^2 + 2x + 1 = 313` `2x^2 + 2x -...

Latest answer posted October 27, 2013 8:16 pm UTC

1 educator answer

Math

A class has 11 boys, 9 girls. Two students will be selected at random to serve on committee. What's probability that...

Given that the number of boys and girls in a class is as follows: Number of boys = 11 Number of girls = 9 Then we conclude that the total number of students in the class= 20 students. Then, the...

Latest answer posted November 29, 2010 7:26 am UTC

1 educator answer

Math

If two resistors with resistances R1 and R2 are connected in parallel, then the total resistance R measured in ohms...

The equivalent resistance of two resistances connected in parallel is given by `1/R = 1/R1 + 1/R2` `R = (R1*R2)/(R1 + R2)` `(dR)/(dt) = ((R1*(dR2)/dt + R2*(dR1)/dt)(R1 + R2) - (R1*R2*((dR1)/dt +...

Latest answer posted March 8, 2012 10:14 pm UTC

1 educator answer

Math

What's the common ratio for 4, 12, 36, 108, ... ?

Hello! A common ratio is a term which applies to a geometric sequence. A geometric sequence starts from any number `a` and any next term is equal to the previous term multiplied by a fixed number...

Latest answer posted January 18, 2016 7:49 am UTC

1 educator answer

Math

1. When 2 dice at thrown, what is the probability of the sum being 9? 2. Two cards are picked at random from a...

Problem 1. When a die is thrown the outcome can be any of the numbers from 1 to 6. If two dice are thrown the set of outcomes that ensure the sum is 9 is {(3, 6), (6,3), (4, 5), (5, 4)}. The total...

Latest answer posted July 30, 2014 7:20 am UTC

1 educator answer

Math

If you are traveling  50 miles at 60mph how long would it take you to get there????

We are traveling at a speed S = 60 m/h The distance we are traveling is D = 50 m We know that: Speed (S) = distance (D)/ Time (T) 60 = 50 / T ==> T = 50/60 = 5/6 hour ==> T = 5/6 * 60 minutes...

Latest answer posted August 3, 2010 12:41 am UTC

1 educator answer

Math

If the radius of a circle is doubled, what effect does this have on the area of the circle? On the circumference? ...

What you have to remember here is the formulas for area and circumference of a circle. The area of a circle is equal to the square of its radius times pi. The circumference of a circle is equal to...

Latest answer posted April 24, 2010 5:49 am UTC

1 educator answer

Math

Twice A Number

The number "x" is represented as a letter because it is a variable. This is the idea of the type of math that is named algebra. Replacing the variables with single letters (sometimes English...

Latest answer posted July 24, 2014 8:50 am UTC

2 educator answers

Math

Find two numbers whose difference is 8 and whose product is a minimum. Find two numbers whose difference is 8 and...

Let x and y be the two numbersWe want x-y = 8 and xy=P as small as possibleAs you wrote, x=8+yOnce you have that, you can substitute into the other equation, and getP=(y+8)y = y^2 + 8yJust as you...

Latest answer posted December 13, 2012 12:39 am UTC

1 educator answer

Math

`5^(2x)+20*5^x-125=0` Solve the equation.

We are asked to solve `5^(2x)+20*5^x-125=0 ` : Rewrite as ` (5^x)^2+20*5^x-125=0 ` and let `y=5^x ` to get ` y^2+20y-125=0` and (y+25)(y-5)=0 so y=-25 or y=5. y cannot be -25 as `5^x>0 ` for all...

Latest answer posted October 28, 2016 4:23 am UTC

1 educator answer

Math

 If a line has no y-intercept, what can you say about the line? What if a line has no x-intercept? Think of a...

If a line has no y-intercept, that means it never intersects the y-axis, so it must be parallel to the y-axis. This means it is a vertical line, such as `x=3` . This slope of this line is...

Latest answer posted September 26, 2012 12:10 am UTC

1 educator answer

Math

Derivative Of E^x

Given f(x) = e^3x We need to find the first derivative f'(x) using the chain rule. We will assume that u= 3x ==> u' = 3 ==> f(x) = e^u ==> Now we will differentiate: ==> f(x) = (e^u)' =...

Latest answer posted March 22, 2011 3:16 am UTC

2 educator answers

Math

Why is it important to learn how to solve inequalities? Does it enhance critical thinking? How can it be applied to...

Inequalities are arguably used more often in "real life" than equalities. Businesses use inequalities to control inventory, plan production lines, produce pricing models, and for...

Latest answer posted August 9, 2013 12:15 pm UTC

2 educator answers

Math

Prove that tanA + tanB + tanC = tanA tanB tanC for any non-right angle triangle

We have to prove that tan A + tan B + tan C = tan A*tan B*tan C for any non-right angle triangle. For any triangle the sum of the angles is equal to 180 degrees. If we take a triangle ABC, A + B +...

Latest answer posted June 5, 2011 10:53 pm UTC

1 educator answer

Math

5/3 As A Mixed Number

A "mixed number," in math terms, is a whole number with a fraction attached to it. What you have posted in your question is essentially an "improper fraction," a situation that occurs when the top...

Latest answer posted November 4, 2009 6:52 am UTC

1 educator answer

Math

Find the nth term of the series 1, 3 , 9 , 27...

Looking at the series of numbers, you can see that any number is 3 times the number right before it. So with each additional term, you have multiplied a number by 3 one more time. This means that...

Latest answer posted July 5, 2012 7:22 pm UTC

2 educator answers

Math

What is the domain and range of the function f(x) = |x - 2|

The domain and range of the function f(x) = |x - 2| has to be determined. The domain of a function is all values of x for which the value of f(x) is defined. The range of the function is all values...

Latest answer posted August 26, 2014 2:26 pm UTC

1 educator answer

Math

How To Solve Y=mx+b

We know the given eqaution y=mx+b represents a straight line with slope m and the y intercept b. So now let us see how to graph the equation y=5x+(-6): Putting x=0, we get y=-6 which implies one...

Latest answer posted July 1, 2015 6:16 am UTC

10 educator answers

Math

How long will your trip take (in hours) if you travel 350 km at an average speed of 80 km\hr? What is the formula...

Hello! The formula for an average speed is a distance travelled divided by a time spent, `V=d/t.` In our problem the average speed `V` and the distance `d` are given, and we are looking for the...

Latest answer posted February 25, 2016 6:48 pm UTC

1 educator answer

Math

How would you write this as an algebraic expression? 49 increased by by twice a number.

You need to focus on the key words in the problem. Increased = go up, add. Twice = two times, double. A number = an unknown number which can be represented by a variable, usually x. Now that you...

Latest answer posted October 20, 2009 12:17 pm UTC

2 educator answers

Math

Why Is Math Important

Math is necessary for even the most basic of life functions. Whether you're buying groceries, determining a budget for yourself, calculating interest on investments, or carrying out a whole myriad...

Latest answer posted January 12, 2009 11:14 am UTC

8 educator answers

Math

Find the point 1/3 of the way from A(2,5) to B(8, -1)

Since we are working with a line, we can look at 1/3 the distance between the x points, and 1/3 the distance between the y points. We have 2 and 8 for our x values, for a distance of 6 units...

Latest answer posted April 17, 2015 5:31 pm UTC

2 educator answers

Math

What is the equation of a line that passes through the point (3,-4) and has a slope of 2?

y + 4=2(x-3) y+4=2x-6 y=2x-10 2x-y-10=0

Latest answer posted September 29, 2009 10:06 am UTC

2 educator answers

Math

What is a term to term rule and a position to term rule in math?

A sequence is an ordered set; usually the objects in the set (often numbers) are written with commas between them. e.g. 1,3,5,7 is a finite sequence, 1,3,5,7,... is an infinite sequence as is...

Latest answer posted May 21, 2013 2:46 pm UTC

1 educator answer

Math

Which is the module of the complex number z = 3 - 4i ? Which is the module of the complex number z = 3 - 4i ?

You should remember that the absolute value of the complex number z is the magnitude of the vector whose coordinates are such that: Hence, evaluating the absolute value of the given complex...

Latest answer posted July 25, 2012 10:36 am UTC

2 educator answers

Math

When 2 dice are thrown the sum of the numbers that turns up is 10. What is the probability that one of the dice has a...

A lot of it has to do with what perspective you are looking at. If you consider the chart on the webpage given, there are 36 combination of rolls you can get from two dice. When you consider the...

Latest answer posted August 8, 2014 2:20 pm UTC

3 educator answers

Math

Given that f(5)=4, f'(5)=5, g(5)=9, g'(5)=8 Calculate (fg)'(5), (f/g)'(5), (g/f)'(5)

It is given that f(5)=4, f'(5)=5, g(5)=9, g'(5)=8 (fg)'(5) = f'(5)*g(5) + f(5)*g'(5) = 5*9 + 4*8 = 45 + 32 = 77 (f/g)'(5) = (f'(5)*g(5) - f(5)*g'(5))/(g(5))^2 = (5*9 - 4*8)/81 = (45 - 32)/81 =...

Latest answer posted March 7, 2012 2:06 am UTC

1 educator answer

Math

What Is The Probability Of Getting A 6 Each Time If A Die Is Rolled 4 Times?

The roll has 6 sides, the probability of rolling a six when the die is rolled once is 1/6 When rolled 4 times, each time has a probability of 1/6. Then the probability is: 1/6 * 1/6 *1/6 *1/6...

Latest answer posted June 25, 2010 10:03 pm UTC

1 educator answer

Math

Express the perimeter P of a square as a function of the area.

We need write the area of a square as a function of the perimeter. Let us write the equation of the perimeter. Let the side of a square be x. Then the perimeter P = 4x. ==> x = P/4 Now we...

Latest answer posted January 17, 2011 10:29 am UTC

1 educator answer

Math

A regular hexagon rotates counterclockwise about its center. It turns through angles greater than 0° and less than or...

Hello! When a hexagon maps onto itself, their vertices must map to vertices and sides to sides. Please look at the picture attached: the nearest vertex for the A1 is A2. There are 6 angles between...

Latest answer posted January 27, 2016 7:21 am UTC

1 educator answer

Math

What happens to the mean of a set of numbers when a zero is added to the set?

When adding a zero to the numbers, the mean will get smaller. Let us prove it by an example. For example: Let "2, 3, 5, 7, 9" be numbers that their mean is as follow. m = (2+ 3 + 5+ 7+ 9) / total...

Latest answer posted November 29, 2010 7:12 am UTC

1 educator answer

Math

Calculate sin^2 1+sin^2 2 +...+ sin^2 90.

We have to find the sum of the series (sin 1)^2 + (sin 2)^2 +...+ (sin 90)^2 (sin 1)^2 + (sin 2)^2 +...+ (sin 90)^2 => (sin 1)^2 + (sin 2)^2 +...+ (sin 90)^2 => (sin 1)^2 + (sin 2)^2 +... +...

Latest answer posted June 21, 2011 1:07 am UTC

1 educator answer

Math

How would you write "The sum of a number and 7" as an algebraic expression?

Your question is very vague so I do hope this answer is sufficient. When you have an unknown quantity, you can call it x,y or any letter actually although x is the most common. Let the unknown...

Latest answer posted March 28, 2013 4:03 pm UTC

1 educator answer

Math

This limit represents the derivative of some function f at some number a. state this f and a. lim h->0  [(4th root...

`(root(4)(16+h)-2)/h` function `f(x)=root(4)(x)` evaluate at a=16 `f(16+h)=root(4)(16+h)` `f(16)=root(4)(16)=2` `(f(16+h)-f(16))/h=(root(4)(16+h)-2)/h` So the answer is `f(x)=root(4)(x)` and `a=16`

Latest answer posted October 3, 2011 2:12 pm UTC

1 educator answer

Math

find the equation of a line parallel to x axis, passing through(3, -6)

We need the equation of a line parallel to the x axis and passing through (3, -6). Now a line parallel to the x-axis is one that has the same value of y for all values of x. As the line required...

Latest answer posted December 15, 2010 8:45 pm UTC

1 educator answer

Math

There are 12 boys and 16 girls in a class. What is the ratio of boys to girls? Write as a fraction in simplest form.

TThe ratio of boys to girls is 12 to 16, 12:16 or 12/16 (all different ways this can be written). The fraction form 12/16 can be reduced by dividing by the greatest common factor. Both 12 and 16...

Latest answer posted November 11, 2008 1:14 pm UTC

1 educator answer

Math

Let F(x)=f(f(x)) and G(x)=(F(x))^2. You also know that f(8)=4, f(4)=3, f'(4)=3, f'(8)=6. Find F'(8) and G'(8)

The derivative `f(f(x))'=f'(x)*f'(f(x))` `F'(8)=f'(8)*f'(f(8))=6*f'(4) ` because `f'(8)=6` and `f(8)=4` `F'(8)=6*3=18` `G'(x)=2F'(x)F(x)` `G'(8)=2F'(8)F(8) ` `F'(8)=18`...

Latest answer posted March 20, 2012 11:47 pm UTC

1 educator answer

Math

Add 1 plus 2 plus 3 plus 4. . . all the way to 100.

We have to find the sum of 1+2+3+. . . +100. Here n=100 We have a formula to calculate the sum of n numbers as: Sum=`(n(n+1))/2` So we have: ` Sum=(100(100+1))/2=5050 ` Hence the sum is 5050.

Latest answer posted October 9, 2017 12:54 am UTC

2 educator answers

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