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x+sin(x) 2020-07-24
From adm:

to evaluate f(30)

use radians only or degrees

Answered by Harley Weston.
Degrees, minutes and seconds 2020-02-21
From Jonathan:
If a cone has an angle of 22 degrees, when i place it flat on a surface, the new resulting central angle is now at 68.69123834, but how come when i saw it on my friend it say 68 degree and 40 minutes, what is this minute?
Answered by Penny Nom.
The degree of 2x + 7 2016-10-17
From Deejay:
How about when the given has no degree and the other has a constant only, For example 2x + 7, where's the leading term and what is its leading coefficient?
Answered by Penny Nom.
tan15° 2016-04-11
From JOHN:
find the exact value of tan15° in surd form.
Answered by Penny Nom.
The degree of a polynomial 2015-01-05
From Nichole:
How do I determine the degree of polynomials? I've searched this on sites but they are all so confusing! Is there a simple explanation or way to find what the degree is? Some examples are: 6x^4 10x^2yz^5 and 3m^2n^7-10m^8. I also have to say that I am under the impression that this symbol ^ means the number after it is an exponent.
Answered by Robert Dawson and Harley Weston.
How many kilometers to a longitudinal degree? 2014-06-19
From cherrielyn:
Assuming that earth is a sphere of radius 6380 km, what is the difference in the latitudes of two cities 270 miles apart positioned on the same meridian?

Thank you in advanced po! :)

Answered by Robert Dawson.
The zeros of a fourth degree polynomial 2013-01-23
From Dakota:
My problem has multiple steps and I have done everything but the last one. 8The original problem is f(x)=x^4-5x^3+7x^2+3x-10 and I have to find the zeros of the equation. I used synthetic substitution like my teacher taught us to get the equation of x^3-3x^2+x+5=0 but now I don't know how to get the zeros of that equation, or solve it.
Answered by Penny Nom.
The derivative of y = sin (30º + x) 2012-11-07
From Saskia:
derivative of y = sin (30º + x)
Answered by Harley Weston.
A bipartite graph 2012-10-29
From A student:
Suppose that G be a bipartite graph with maximum degree of k.

Prove that:

1)Exists a K-regular bipartite graph that G be subgraph it(H)

Answered by Claude Tardif.
The degree measure of the central arc of a circle 2012-10-17
From Crystal:
On a circle with radius of 12 cm is an arc of length 20 cm. What is the degree measure of the central angle used to make this arc?
Answered by Penny Nom.
A tapestry rod on a curved wall 2012-08-14
From Marlyn:
I have a curved wall with a radius of 6'. I am trying to have a 36" rod made to hang a tapestry and need to figure out the degree measure of the arc. Can you help me please?
Answered by Penny Nom.
Angle measures 2012-03-21
From jogiboy:
how can i get the sine theta if the given is 3.14/3
Answered by Penny Nom.
Construct a 30 degree angle 2011-06-10
From Ella:
they give you a simple straight line and ask you to construct an angle of 30 degrees at one end of the line using only a ruler and a compass?
Answered by Penny Nom.
The degree measure of an arc in a circle 2011-04-08
From Deb:
How do I find the degree measure of an arc in a circle with the Length of 14 and the radius of 70?
Answered by Penny Nom.
The rate of change of the area of a parallelogram 2011-04-05
From Gevork:
Let a parallelogram have sides of 8 and 12 and let vertex angle A be decreasing at a rate of 2degrees per minute. Find the rate of change of the area of the parallelogram when angle A equals 30 degrees.
Answered by Penny Nom.
Identify each polynomial by its degree and number of terms 2011-01-10
From betty:
Write in standard form and identify each polynomial by its degree and number of terms. How do you do this?
Answered by Penny Nom.
z^5 - 3z^4 + 2z^3 + z^2 - 3z + 2 2010-11-06
From Kumar:
would you please solve this problem, related to complex numbers.

Find all the roots of :

z^5 - 3z^4 + 2z^3 + z^2 - 3z + 2

Answered by Robert Dawson and Penny Nom.
A cylinder is cut at an angle of 20 degrees 2010-01-25
From sanjay:
If I have a cylinder with 40mm diameter and I will cut it at an angle 20 degrees so what would be the increased radius or dia.??? of the cylinder
Answered by Penny Nom.
Fourth and fifth degree polynomials 2009-08-20
From Evin:
hello.i am a student . ax^4+bx^3+cx^2+dx+e=0 x=? i want to learn the solution or formula of equations of the fourth and fifth degree...PLEASE
Answered by Robert Dawson.
The sum of the angles of a triangle 2009-05-18
From mary:
prove that the sum of the three angles inside any triangle always add up to 180 degrees?
Answered by Harley Weston.
How many feet does a shadow move per hour? 2009-04-02
From Zora:
How many feet does a shadow move per hour?
Answered by Robert Dawson.
A simple digraph 2009-03-23
From Shabkhal:
Show that the sum of in degrees of all the nodes of a simple digraph is equal to the sum of out degrees of all its nodes and this sum is equal to the number of edges of the graph.
Answered by Victoria West.
limit sinx/x 2009-01-30
From Jackie:
how to evaluate limit sinx/x as x tends to zero if x is in degrees
Answered by Stephen La Rocque and Harley Weston.
1 foot drop every 25 feet 2009-01-22
From jerry:
1 foot drop every 25 feet what is the angle of the degree
Answered by Penny Nom.
Cutting a pipe on a 45 degree angle 2008-09-12
From Bakshani:
how do you a mark a pipe 5 inch diameter and cut it to form a 45 degree angel
Answered by Stephen La Rocque.
What angle should he turn? 2007-12-01
From Jasmine:
Bob is traveling due north he then turns left 45 degrees followed by four 20 degree turns to the right

What is his new heading if he needed to turn so his heading was SSW what direction and what angle should he turn?

Answered by Walter Whiteley.
Is there a practical use for radian measure? 2007-10-26
From Paula:
Is there a practical use for radian measure in any profession? Which professions might us radian as opposed to degree measure?
Answered by Harley Weston.
More on the sixth degree equation 2007-08-21
From Farzan:
Equation 1 :
(R + (6.67*5.98*10^13/((R^2)*2)))^2 - (R^2) = (7.27*(10^-5)*R)^2
Equation 2 :
(6.67*5.98*10^13/(R^2*2))^2 + 6.67*5.98*10^13/R = (7.27*10^-5*R)^2
As you see if we expand the left part of the first equation and simplify, the equations become same, but these two equations have different answers in my math software.The first one has 3 amounts for R, but the second one has 6 amounts. Why are the answers different ?

Answered by Stephen La Rocque.
A sixth degree equation 2007-08-20
From Farzan:
Dear friends I need to solve this equation with an understandable method for high-school students : (6.67*5.98*10^13/(R^2*2))^2 + 6.67*5.98*10^13/R = (7.27*10^-5*R)^2 please solve this problem if you have time.
Answered by Harley Weston.
Angle of clock hands 2007-01-31
From Sophia:
How many degrees are in the aute angle formed by the hands of a clock at 2:20 p.m.?
Answered by Stephen La Rocque.
a _________________ line forms a 90 degree angle with another line 2006-09-24
From Lisa:
a _________________ line forms a 90 degree angle with another line is this to it what fills in the blank? first letter is E third letter is R and has 13 letters
Answered by Stephen La Rocque.
The product of polynomials 2006-07-13
From Lynne:
If you multiply two polynomials, what can you say about the degree of their product? What exponent applies here?
Answered by Stephen La Rocque.
Fahrenheit and Celsius 2006-06-12
From Doris:
I just know how to do problems with fahrenheit or celcius. Could you show me step by step how to do these? Then I can do it if you can show me each step of the way.
Answered by Stephen La Rocque and Penny Nom.
Degrees and grads 2006-04-06
From Nazanin:
which angle if you add 15 to its degree we can find its measure by grad?
Answered by Stephen La Rocque.
Degree 2006-02-09
From Jessica:
I am a 9th grade home school student and have started doing degrees of terms in my math book. The following is some examples they give:

25a to the 4th power is a 4th degree term

67c to the 9th power is a 9th degree term

x is really x to the 1st power so it is a 1st degree term

10 is really 10x to the 0 power so it is a 0 degree term

They go on to say that every constant is a zero degree term.

My question is why isn't a constant, like 10, simply to the 1st power (making is a 1st degree term) like x.

Answered by Claude Tardif.
The degree sequence of a graph 2004-03-31
From Ali:
How can i find out {6,6,5,5,5,3,2}is not the sequence of the points of a simple graph,without drawing it?
Answered by Penny Nom.
Cosine of 35 degrees 2004-03-03
From Jason:
How do you find the exact solution to cosine 35 degrees.
Answered by Chris Fisher.
Polynomials degree 4 and bigger 2003-06-26
From Stephen:

How do I show kids how to find all the zeros for polynomials degree 4 and bigger.

For examples:
r(x) = x5-11x3-7x2+77 = (x2-11)(x3-7) and s(x) = x4-121 = (x2-11)(x2+11)

Also am I correct when I say that the following are irreducible?

f(x) = x2-11
g(x) = x3-7
h(x) = x4-5

Answered by Harley Weston.
Radians 2003-01-16
From Erikson:
I am a student in the 10th grade and attending advanced math at my high school. I was assign to do a report about the unit circle and the radian. But there seems to be no information available about the history of the radian; who first found out about them, which civilizations used it if any. Well, hopefully you'll assist me in this troubling question. Thank you for your kind consideration.
Answered by Penny Nom.
A polynomial 2002-04-14
From A student:
A polynomial function is described by the following conditions: f(x) has two real zeros at x= -2 and x= 1, each of multiplicity 2 f(x) has two complex zeros as x goes to -infinity, f(x) goes to +infinity as x goes to +infinity, f(x) goes to +infinity f(x) has a y-intercept at (0,2)

Sketch a polynomial function that satisfies the above conditions.

Write an equation for function f(x)

Write another function g(x) that also satisfies the above parameters.

Answered by Penny Nom.
A degree 5 polynomial 2002-02-17
From Carla:
Write an equation for a polynomial of degree 5 given the following zeros:
-7+3i, -2+sqrt(13), 6

Answered by Penny Nom.
Why quadratic for a second degree equation? 2001-10-20
From Jana:
Why do we use the word quadratic to describe second degree equations?
Answered by Penny Nom.
Radian measure 2001-07-26
From Amy:
i have to find out what is meant by the radian measure of an angle and compare it to the measure of an angle in degrees.
Answered by Harley Weston.
Law of cosines 2001-02-20
From Emily:
I missed a few days of class and I can't figure out how to solve Law of Cosines problems. I have the notes and formulas but I can't figure out how to do the math involved to answer the problems. I am also getting confused about how to use degrees and seconds in the Law of Sine and Cosine. I can't seem to get the correct answers and I don't really know how to solve them and enter them into my TI 86.
Answered by Harley Weston.
Motivators 2001-01-16
From Michelle Stapley:
Do you know of any (or where I can find) student motivators for math at the secondary level? Basically any way I can motivate my students to WANT to learn math.
Answered by Penny Nom.
The side length ratios of some triangles 2000-04-04
From Alexis Lockwood:
I am doing a project for my Math 30B class regarding the side length ratios of 45-45-90 degree and 30-60-90 degree triangles. I would really appreciate any assistance in answering the following questions, or even direction to an appropriate web site or resource on the matter.
Answered by Harley Weston.
Careers after a math degree 2000-03-31
From Jeanne Hyer:
What type of careers can a person have with a math degree, and what is the closest thing that you have to an undergraduate degree in financial mathematics? (Administration, math, actuarial science, etc.)
Answered by Harley Weston.
Specific heat 1999-12-22
From Irena:
In transferring 1260J of heat to water, the temperature of 0.20 kg of mercury falls 50 K. Calculate the specific heat capacity of mercury using the equation C= Q/(m)(delta t)

i know that Q= -1260J because it's loosing heat and m= 0.2kg and since i have to use 'C i have to convert Kelvins into Celsius (i also know that 'C has to be negative since it looses heat)
Answered by Harley Weston.

Degrees and triangles 1999-09-09
From Sandra Mills:
Are there any triangles which are not 180 degrees?

I am also in need of information on the history of degree measure for an angle.
Answered by Walter Whiteley.

Question about 3rd degree polynomials 1999-04-23
From Patrick Bryan:
What is the general solution to the equation with the form:

a*x^3 + b*x^2 + c*x + d = 0

I have once seen a solution to this a few years ago, but I do not recall if it was a general solution. What I do know, is that you could simplify this equation to:

a*x'^3 + p*x' + q = 0...
Answered by Doug Farenick.

The sum of the angles of a triangle is 180 degrees 1998-02-19
From Quin Liu:
How do you prove that the sum of the angles of a triangle is 180 degrees? Is there a proof? what is it?
Answered by Chris Fisher.
Trigonometric functions 1997-12-21
From Calvin Cheng:
My name is Calvin and I have a year 12 question for you to help me with.

From a point S, the angle of elevation of the top of a tower due north of it is 20 degrees. From R, due east of the tower, the angle of elevation is 18 degrees. S and R are 100m apart. Find the height of the tower.
Answered by Harley Weston.

Why is a circle divided into 360 degrees? 1996-09-30
From Kurtis Kredo:
I was recently wondering why a circle has been divided in to 360 degrees. When I asked my physics teacher he could not think of an answer. His guess is that it probably has to do with people long ago using the base 6 number system. I have a small inkling that it has to do with easy conversion or usage with radians or grads.
Answered by Chris Fisher.
Un polynome de degré 3 2010-10-09
From ait:
comment determiner n polynome P de degré 3 verifiant pour tout reel x la relation p(x+1)-p(x)=x²
Answered by Claude Tardif.



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